tutor

                  _   _                 __    __
                 | | | |         _      \ \  / /
                 | |_| |   ___  | | (_)  \ \/ /
                 |  _  |  / _ \ | |  _    )  (
                 | | | | |  __/ | | | |  / /\ \
                 |_| |_|  \___| |_| |_| /_/  \_\

                 A post-modern modal text editor.
_________________________________________________________________

 Welcome to the Helix editor! Helix is different from editors
 you might be used to in that it is modal, meaning that it has
 different modes for editing text. The primary modes you will
 use are Normal mode and Insert mode. While in Normal mode, the
 keys you type won't actually type text. Instead, they will
 perform various actions with the text. This allows for more
 efficient editing. This tutor will teach you how you can make
 use of Helix's modal editing features. To begin, ensure your
 CapsLock key is not pressed and hold the j key until you reach
 the first lesson.


=================================================================
=                  1.1 BASIC CURSOR MOVEMENT                    =
=================================================================

          ↑
          k       * h is on the left
      ← h   l →   * l is on the right
          j       * j looks like a down arrow
          ↓

 The cursor can be moved using the h, j, k, l keys, as shown
 above. The cursor / arrow keys will also work, but it is faster
 to use the hjkl keys as they are closer to the other keys you
 will be using. Try moving around to get a feel for hjkl.
 Once you're ready, hold j to continue to the next lesson.







=================================================================
=                      1.2 EXITING HELIX                        =
=================================================================

 1. Type : to enter Command mode. Your cursor will
    move to the bottom of the screen.
 2. Type q or quit and type Enter to exit Helix.

 Note: The quit command will fail if there are unsaved changes.
       To force quit and DISCARD these changes, type q! or quit!.
       You will learn how to save files later.

 To exit Command mode without entering a command, type Escape.

 Now, move on to the next lesson.







=================================================================
=                         1.3 DELETION                          =
=================================================================

 Type the d key to delete the character under the cursor.

 1. Move the cursor to the line marked '-->' below.
 2. Move the cursor to each extra character, and type d to
    delete it.

 --> Thhiss senttencee haass exxtra charracterss.
     This sentence has extra characters.

 Once the sentence is correct, move on to the next lesson.








=================================================================
=                       1.4 INSERT MODE                         =
=================================================================

 Type the i key to enter Insert mode.

 1. Move the cursor to the line marked '-->' below.
 2. Move to a place in the line which is missing text and type
    i to enter Insert mode. Keys you type will now type text.
 3. Enter the missing text.
 4. type Escape to exit Insert mode and return to Normal mode.
 5. Repeat until the line matches the line below it.

 --> Th stce misg so.
     This sentence is missing some text.

 Note: The status bar will display your current mode.
       Notice that when you type i, 'NOR' changes to 'INS'.




=================================================================
=                      1.5 SAVING A FILE                        =
=================================================================

 Type :w / :write to save a file.

 1. Exit Helix using :q! as explained before, or open a new
    terminal.
 2. Open a file in Helix by running: hx FILENAME
 3. Make some edits to the file.
 4. Type : to enter Command mode.
 5. Type w or write, and type Enter to save the file.

 You can also type wq or write-quit to save and exit.

 Note: You can optionally enter a filepath after the w / write
       command in order to save to that path.
 Note: If there are any unsaved changes to a file, a plus [+]
       will appear next to the file name in the status bar.



=================================================================
=                        CHAPTER 1 RECAP                        =
=================================================================

 * Use the h,j,k,l keys to move the cursor.

 * Type : to enter Command mode.
   * The q / quit and q! / quit! commands will exit Helix. The
     former fails when there are unsaved changes. The latter
     discards them.
   * The w / write command will save the file.
   * The wq / write-quit command will do both.

 * Type d to delete the character at the cursor.

 * Type i to enter Insert mode and type text. Type Escape to
   return to Normal mode.





=================================================================
=                   2.1 MORE INSERT COMMANDS                    =
=================================================================

 As you saw, you can type i to enter Insert mode at the current
 position of the cursor. There are a few other ways you can
 enter Insert mode at different locations.

 Common examples of insertion commands include:
   i - Insert before the selection.
   a - Insert after the selection. (a means 'append')
   I - Insert at the start of the line.
   A - Insert at the end of the line.

 1. Move to anywhere in the line marked '-->' below.
 2. Type A (Shift-a), your cursor will move to the end of
    the line and you will be able to type.
 3. Type the text necessary to match the line below.

 --> This sentence is miss
     This sentence is missing some text.

=================================================================
=                      2.2 OPENING LINES                        =
=================================================================

 Type o to add a newline and insert below the cursor.
 Type O to add a newline and insert above the cursor.

 1. Move the cursor to the line marked '-->' below.
 2. Type o to open a line below and type your answer.

 --> What is the best editor?











=================================================================
=                        CHAPTER 2 RECAP                        =
=================================================================

 * Type a to append to the selection.

 * Type I to enter Insert mode at the first non-whitespace
   character at the start of a line.

 * Type A to enter Insert mode at the end of a line.

 * Use o and O to open lines below and above the cursor respectively.










=================================================================
=                  3.1 MOTIONS AND SELECTIONS                   =
=================================================================

 Type w to select forward until the next word.

 The d key doesn't actually delete the character at the cursor,
 it deletes all selected text. Your cursor is like a
 single-character selection.

 1. Move the cursor to the line marked '-->' below.
 2. Move to the beginning of a word that needs to be deleted.
 3. Type w to select until the beginning of the next word.
 4. Type d to delete the selection.
 5. Repeat for all extra words in the line.

 --> This sentence pencil has vacuum extra words in the it.
     This sentence has extra words in it.




=================================================================
=                     3.2 MORE ON MOTIONS                       =
=================================================================

 As you saw, typing w moves the cursor forward until the start
 of the next word, selecting the text traversed. This is useful
 for moving around text and for selecting text to operate on.

 Some common motions include:
   w - Move forward to before the beginning of the next word.
   e - Move forward to the end of the current word.
   b - Move backward to the beginning of the current word.

 The w,e,b motions also have counterparts - W,E,B - which
 traverse WORDS instead of words. WORDS are only separated by
 whitespace, whereas words can be separated by other characters
 in addition to whitespace.

 All of these motions select the text they traverse.



=================================================================
=                    3.3 THE CHANGE COMMAND                     =
=================================================================

 Type c to change the current selection.

 The change command deletes the current selection and enters
 Insert mode, so it is a very common shorthand for di.

 1. Move the cursor to the line marked '-->' below.
 2. Move to the start of an incorrect word and type w to
    select it.
 3. Type c to delete the word and enter Insert mode.
 4. Type the correct word.
 5. Repeat until the line matches the line below it.

 --> This paper has heavy words behind it.
     This sentence has incorrect words in it.




=================================================================
=                   3.4 COUNTS WITH MOTIONS                     =
=================================================================

 Type a number before a motion to repeat it that many times.

 1. Move the cursor to the line marked '-->' below.
 2. Type 2w to move 2 words forward.
 3. Type 3e to move to the end of the third word forward.
 4. Type 2b to move 2 words backwards
 5. Try the above with different numbers.

 --> This is just a line with words you can move around in.









=================================================================
=                    3.5 SELECT / EXTEND MODE                   =
=================================================================

 Type v to enter Select mode.
 Type v again or Escape to return to Normal mode
 In Select mode every movement will extend the selection, as
 opposed to replacing it.

 1. Move the cursor to the line marked '-->' below.
 2. Move to the F of FOO and type v2w to select the two words.
 3. Type d to remove the two words. Notice d returns you to
    Normal mode.
 4. Move to the B of BAZ and repeat the sequence to delete them.

 --> Remove the FOO BAR distracting words BAZ BIZ from this line.






=================================================================
=                     3.6 SELECTING LINES                       =
=================================================================

 Type x to select a whole line. Type x again to select the next.

 1. Move the cursor to the second line marked '-->' below.
 2. Type x to select the line, and d to delete it.
 3. Move to the fourth line.
 4. Type x twice or type 2x to select 2 lines, and d to delete.

 --> 1) Roses are red,
 --> 2) Mud is fun,
 --> 3) Violets are blue,
 --> 4) I have a car,
 --> 5) Clocks tell time,
 --> 6) Sugar is sweet,
 --> 7) And so are you.

 Note : X works similarly to x although it doesn't extend to
      subsequent lines. X on an empty line does nothing.

=================================================================
=                   3.7 COLLAPSING SELECTIONS                   =
=================================================================

 Type ; to collapse selections to single cursors.

 Sometimes, you want to deselect without having to move the
 cursor(s). This can be done using the ; key.

 1. Move the cursor to the line marked '-->' below.
 2. Use the motions you have learned to move around the line,
    and try using ; to deselect the text after it is selected
    by the motions.

 --> This is an error-free line with words to move around in.

 Note: This works the same in Select mode.
 Note: Another related command is Alt-; which flips selections.




=================================================================
=                        CHAPTER 3 RECAP                        =
=================================================================

 * Type w to select forward until the next word.
   * Type e to select to the end of the current word.
   * Type b to select backward to the start of the current word.
   * Use uppercase counterparts, W,E,B, to traverse WORDS.

 * Type d to delete the entire selection.
   * Type c to delete the selection and enter Insert mode.

 * Type a number before a motion to repeat it that many times.

 * Type v to enter Select mode, where all motions extend the
   selection.

 * Type x to select the entire current line. Type x again to
   select the next line.

 * Type semicolon ( ; ) to collapse selection.

=================================================================
=                         4.1 UNDOING                           =
=================================================================

 Type u to undo. Type U to redo.

 1. Move the cursor to the line marked '-->' below.
 2. Move to the first error, and type d to delete it.
 3. Type u to undo your deletion.
 4. Fix all the errors on the line.
 5. Type u several times to undo your fixes.
 6. Type U (Shift-u) several times to redo your fixes.

 --> Fiix the errors on thhis line and reeplace them witth undo.








=================================================================
=                 4.2 COPYING AND PASTING TEXT                  =
=================================================================

 Type y to yank (copy) the selection.
 Type p to paste the yanked selection after the cursor.
 Type P to paste the yanked text before the cursor.

 1. Move the cursor to the line marked '-->' below.
    Make sure your cursor is on the "b" of banana.
 2. Type w to select "banana" and y to yank it.
 3. Move to the space between "2" and "3" and type p to paste.
 4. Repeat between "3" and "4".

 --> 1 banana 2 3 4
     1 banana 2 banana 3 banana 4

 Note: Whenever you delete or change text, Helix will copy the
       altered text. Use Alt-d / Alt-c instead to avoid this.
 Note: Helix doesn't share the system clipboard by default. Type
       Space + y / p to yank / paste on the system's clipboard.

=================================================================
=                     4.3 SEARCHING IN FILE                     =
=================================================================

 Type / to search forward in file, Enter to confirm search.
 Type n to go to the next search match.
 Type N to go to the previous search match.

 1. Type / and type in a common word, like 'banana'.
 2. Type Enter to confirm the search.
 3. Use n and N to cycle through the matches.

 Searching uses regular expressions, allowing you to target more
 complex expressions, which you'll learn about in the lesson on
 the select command.

 Note: To search backwards, type ? (Shift-/).
 Note: Unlike Vim, ? doesn't change the search direction.
       N always goes backwards and n always goes forwards.



=================================================================
=                        CHAPTER 4 RECAP                        =
=================================================================

 * Type u to undo. Type U to redo.

 * Type y to yank (copy) text and p to paste.
   * Use Space + y and Space + p to yank / paste on the system
     clipboard.

 * Type / to search forward in file, and ? to search backwards.
   * Use n and N to cycle through search matches.










=================================================================
=                     5.1 MULTIPLE CURSORS                      =
=================================================================

 Type C to duplicate the cursor to the next suitable line.

 1. Move the cursor to the first line marked '-->' below. Place
    the cursor somewhere past the '-->'.
 2. Type C to duplicate the cursor to the next suitable line.
    Notice how it skips the line in the middle. Keys you type
    will now affect both cursors.
 3. Use Insert mode to correct the lines. The two cursors will
    fix both lines simultaneously.
 4. Type , to remove the second cursor.

 --> Fix th two nes at same ime.
 -->
 --> Fix th two nes at same ime.
     Fix these two lines at the same time.

 Note: Type Alt-C to do the same above the cursor.

=================================================================
=                    5.2 THE SELECT COMMAND                     =
=================================================================

 Type s to select matches in the selection.

 1. Move the cursor to the line marked '-->' below.
 2. Type x to select the line.
 3. Type s. A prompt will appear.
 4. Type 'apples' and type Enter. Both occurrences of
    'apples' in the line will be selected.
 5. You can now type c and change 'apples' to something else,
    like 'oranges'.
 6. Type Escape to exit Insert mode.
 7. Type , to remove the second cursor.

 --> I like to eat apples since my favorite fruit is apples.
     I like to eat oranges since my favorite fruit is oranges.




=================================================================
=                    5.3 SELECTING VIA REGEX                    =
=================================================================

 Like searching, the select command selects regular expressions,
 not just exact matches.

 1. Move the cursor to the line marked '-->' below.
 2. Select the line with x and then type s.
 3. Enter '  +' to select any amount of consecutive spaces >1.
 4. Type c and change the matches to single spaces.

 --> This  sentence has   some      extra spaces.
     This sentence has some extra spaces.

 Note: If you want to perform find-and-replace, the select
       command is the way to do it. Select the text you want
       to replace in — type % to select the whole file — and
       then perform the steps explained above.



=================================================================
=                      5.4 ALIGN SELECTIONS                     =
=================================================================

 Type & to align the contents of the selections.

 1. Move the cursor to the first line marked '-->' below. Place
    the cursor on the whitespace just after the arrow.
 2. Type C four times or 4C.
 3. Type W to select the numbers and brackets.
 4. Type & to align the words.

 --> 97) lorem
 --> 98) ipsum
 --> 99) dolor
 --> 100) sit
 --> 101) amet

 Note: & only cares about the alignment of the "head" of the
       selections - the end that moves. The other end is called
       the "anchor".

=================================================================
=                 5.5 SPLIT SELECTION INTO LINES                =
=================================================================

 Type Alt-s to split the selection(s) on newlines.

 1. Move the cursor to the first row of the table below.
 2. Select the entire table with 6x.
 3. Type Alt-s to split into selections at each line.
 4. Align the table with &.

    | FRUIT   | AMOUNT |
    |---------|--------|
 | Apples  | 8      |
    | Bananas | 6      |
  | Oranges | 3      |
     | Donuts  | 4      |





=================================================================
=                        CHAPTER 5 RECAP                        =
=================================================================

 * Type C to duplicate the cursor to the next suitable line
   and Alt-C for previous suitable line.

 * Type s to select all instances of a regex pattern inside
   the current selection.

 * Type & to align selections.

 * Type Alt-s to split the selection into lines.









=================================================================
=                 6.1 SELECTING TO A CHARACTER                  =
=================================================================

 Type f<ch> to select up to and including (find) a character.
 Type t<ch> to do the same, but not including (till) a character.
 Type uppercase F / T to do the same backwards.

 1. Move the cursor to the line marked '-->' below. Place the
    cursor on the first dash.
 2. Type f[ to select to the square bracket.
 3. Type d to delete your selection.
 4. Go to the end of the line and repeat with F].
 5. Move to the second line marked '-->', just after the arrow.
 6. Use t and T to delete the dashes around the sentence.

 --> -----[Free this sentence of its brackets!]-----
 --> ------Free this sentence of its dashes!------

 Note: Unlike Vim, Helix doesn't limit these commands to the
       current line. It searches for the character in the file.

=================================================================
=                    6.2 THE REPLACE COMMAND                    =
=================================================================

 Type r<ch> to replace all selected characters with <ch>.

 1. Move to the second line of the table, place the cursor on the
    first =.
 2. Type t| (Shift-\) to select the = separator.
 3. Type r- to replace the separator with dashes.


 | Month | Days |
 |=======|------|
 | Jan   | 31   |
 | Feb   | 28   |
 | Mar   | 31   |
 | ...   | ...  |




=================================================================
=                         6.3 REPETITION                        =
=================================================================

 Type . to repeat the last insert command.
 Type Alt-. to repeat the last f / t selection.

 1. Move the cursor to the line marked '-->' below.
 2. Make a change, insertion or appendage and repeat it with . .
 3. Try using Alt-. with f and t, to select multiple sentences
    for instance.

 --> This is some text for you to repeat things. You can repeat
     insertions like changing words, or repeat selections like
     f / t.







=================================================================
=                        CHAPTER 6 RECAP                        =
=================================================================

 * Type f / F to extend selection up to & including a character.
   * Type t / T to extend selection until a character.

 * Type r to replace selected characters.

 * Type . to repeat the last insertion.
   * Type Alt-. to repeat the last f / t selection.











=================================================================
=                  7.1 REPLACE WITH YANKED TEXT                 =
=================================================================

 Type R to replace the selection with previously yanked text.

 1. Move the cursor to the line marked '-->' below.
 2. Type w to select "watermelons" and then y to yank it.
 3. Select "oranges" with w.
 4. Type R to replace "oranges" with "watermelons"


 --> I like watermelons because oranges are refreshing.
     I like watermelons because watermelons are refreshing.








=================================================================
=                       7.2 JOINING LINES                       =
=================================================================

 Type J to join together lines in selection.

 1. Move the cursor to the line marked '-->' below.
 2. Type x four times or 4x to select all four lines.
 3. Type J to join the lines together.

 --> This sentence
is spilling over
onto other
lines.

     This sentence is spilling over onto other lines.






=================================================================
=                      7.3 INDENTING LINES                      =
=================================================================

 Type > to indent a line and < to outdent it.

 1. Move the cursor to the line marked '-->' below.
 2. Move down to the second line and type > to indent it.
 3. Move to the third line and type < to outdent it.

 --> These lines
    are indented
         very poorly.

     These lines
     are indented
     much better.





=================================================================
=               7.4 INCREMENTING AND DECREMENTING               =
=================================================================

 Type Ctrl-a to increment the number under selection.
 Type Ctrl-x to decrement the number under selection.

 1. Move the cursor to the third line marked '-->' below.
 2. Type Ctrl-a to increment the second point marked 2.
 3. Repeat for the point marked 3.
 4. Move to the last point and type Ctrl-x to decrement the 6.

 --> 1) First point.
 --> 2) Added point.
 --> 2) Next point.
 --> 3) Another point.
 --> 6) Last point.

 Note: If there isn't a number under the selection the cursor
       will jump to the next number in the line and act on it.


=================================================================
=                        CHAPTER 7 RECAP                        =
=================================================================

 * Type R to replace the selection with yanked text.

 * Type J to join lines in selection.

 * Type < and > to indent / outdent lines.

 * Type Ctrl-a to increment the selected number.
   * Type Ctrl-x to decrement the selected number.










=================================================================
=                         8.1 REGISTERS                         =
=================================================================

 Registers are containers identified by a character for storing
 things like yanked text. Registers are also used to store the
 most recent search term as well as macros, which you'll learn
 about in the next section.

 Type "<ch> to select register <ch>.

 1. Move the cursor to the line marked '-->' below.
 2. Type w to select "watermelons" and yank with y.
 3. Type w to select "bananas".
 4. Change to register b with "b and yank with y.
 5. Select "mangoes" and type R to replace it with "watermelons".
 6. Select "pineapples" then type "b R to replace with "bananas".

 --> I like watermelons and bananas because my favorite fruits
     are mangoes and pineapples.


=================================================================
=                          8.2 MACROS                           =
=================================================================

 Macros are a way to record a set of actions you want to repeat.
 You can also record macros to a specific register (default @).
 Type Q to start recording a macro - you should see a popup at
 the bottom of your screen. Type Q again to stop recording.
 Type q to repeat the macro from register @ (the default).

 1. Move the cursor to the first line marked '-->' below.
    Ensure your cursor is on the > of the arrow.
 2. Type Q to start recording.
 3. Edit the line to look like the bottom one.
 4. Exit insert and Type Q again to stop recording.
 5. Move to the line below and put your cursor on the > again.
 6. Type q to repeat the macro.

 --> ... sentence doesn't have it's first and last ... .
 --> ... sentence doesn't have it's first and last ... .
     This sentence doesn't have it's first and last word.

=================================================================
=                        CHAPTER 8 RECAP                        =
=================================================================

 * Type " to select a different register.

 * Type Q to start and stop recording a macro to a register,
   the default being @.

 * Type q to replay a macro from @ or the selected register.












=================================================================
=                  9.1 SEARCHING FOR SELECTIONS                 =
=================================================================

 The most recent search with / is stored in register /.
 n and N both refer to register /, this means we can set that
 register without having to type in a search.

 Type * to copy the selection into register /, setting the search
 term to the selection. This copies the primary selection, which
 you will learn about in the section on cycling selections.

 1. Move the cursor to the line marked '-->' below.
 2. Select "horse" with e and type *.
 3. Use n and N to jump between the instances of "horse".

 --> A horse is a horse, of course, of course,
 --> And no one can talk to a horse of course.

 Note: * is like a shorthand for "/ y as all it really does is
       copy the selection into the / register.

=================================================================
=           9.2 ADDING SELECTION ON NEXT SEARCH MATCH           =
=================================================================

 A property of Select mode (v) when using n and N is that instead
 of moving the selection to the next match, it adds a new
 selection on each match.

 1. Move the cursor to the line marked '-->' below.
 2. Select the first "bat" and type * to set it to search.
 3. Type v to enter Select mode.
 4. Type n to select the other "bat".
 5. Use c or r to change the "bat"s to "cat".

 --> Everybody wants to be a bat,
 --> because a cat's the only bat
 --> who knows where it's at.





=================================================================
=                     9.3 USING THE JUMPLIST                    =
=================================================================

 Helix can keep track of "jumps" which are big movements, like
 searching or jumping to the definition of a function in code. It
 stores these in what's called the jumplist.

 Type Ctrl-s to manually save your current position to
 the jumplist.

 Type Ctrl-i ("in") and Ctrl-o ("out") to move forward and
 backwards in the jumplist respectively.

 1. Type Ctrl-s somewhere.
 2. Move far away in the file.
 3. Type Ctrl-o (just once!) to come back to where you saved.





=================================================================
=                        CHAPTER 9 RECAP                        =
=================================================================

 * Type * to set the search register to the primary selection.

 * Type n / N in Visual mode to add selections on each search
   match.

 * Type Ctrl-s to save position to the jumplist.
   * Type Ctrl-i and Ctrl-o to go forward and backward in the
     jumplist.










=================================================================
=             10.1 CYCLING AND REMOVING SELECTIONS              =
=================================================================

 Type ) and ( to cycle the primary selection forward and backward
 through selections respectively.

 Type Alt-, to remove the primary selection.

 1. Move the cursor to the line marked '-->' below.
 2. Select both lines with xx or 2x.
 3. Type s to select, type "would" and enter.
 4. Use ( and ) to cycle the primary selection and remove the
    very second "would" with Alt-, .
 5. Type c "wood" to change the remaining "would"s to "wood".

 --> How much would would a wouldchuck chuck
 --> if a wouldchuck could chuck would?

 Note: Additionally, Alt-( and Alt-) cycle the *contents* of the
       selections as well.

=================================================================
=                     10.2 CHANGING CASE                        =
=================================================================

 Type ~ to switch the case of all selected letters.
 Type ` to set all selected letters to lowercase.
 Type Alt-` to set all selected letters to uppercase.

 1. Move the cursor to the first line marked '-->' below.
 2. Select each wrongly capitalised or lowercase letter
    and type ~ over them.
 3. Move to the second line marked '-->'.
 4. Type x to select the line.
 5. Type ` to change the line to lowercase.
 6. Move to the third line marked '-->'.
 7. Type x to select the line.
 8. Type Alt-` to change the line to uppercase.

 --> thIs sENtencE hAs MIS-cApitalIsed leTTerS.
 --> this SENTENCE SHOULD all be in LOWERCASE.
 --> THIS sentence should ALL BE IN uppercase!

=================================================================
=                   10.3 SPLITTING SELECTIONS                   =
=================================================================

 Type S to split each selection on a regex pattern.

 1. Move the cursor to the line under ---.
 2. Type xx / 2x to select the lines.
 3. Type S then \. |! Enter (note the spaces after . and !).
    This effectively splits the selection into sentences at each
    dot or exclamation mark.
 4. Type Alt-; to reverse the selections.
 5. Type ; to reduce selections to a single character - the first
    letter of each sentence.
 6. Type Alt-` to convert all selected letters to uppercase.

---
these are sentences. some sentences don't start with uppercase
letters! that is not good grammar. you can fix this.



=================================================================
=                        CHAPTER 10 RECAP                       =
=================================================================

 * Use ) and ( to cycle the primary selection back and forward
   through selections respectively.
   * Type Alt-, to remove the primary selection.

 * Type ~ to alternate case of selected letters.
   * Use ` and Alt-` to set the case of selected letters to
     upper and lower respectively.

 * Type S to split selections on regex.









=================================================================
=                                                               =
=================================================================















=================================================================
 This tutorial is still a work-in-progress.
 More sections are planned.