Unicode.vim

Default Vim Unicode Input

To enter Vim's default Unicode input mode, ensure you are in <INSERT> mode and press <Ctrl>+V. Then proceed to enter your character code following the guidelines below -

# Vim character sequence prefix codes
a decimal number (0-255)
o then an octal number (o0-o377, i.e., 255 is the maximum value)
x then a hex number (x00-xFF, i.e., 255 is the maximum value)
u then a 4-hexchar Unicode sequence
U then an 8-hexchar Unicode sequence

So, if we wanted the stopwatch - f2f2 symbol from Font Awesome's Cheatsheet, we would enter <INSERT> mode within Vim and press <Ctrl>+V, followed by the character keypresses respective to our (4-char) unicode symbol - u+f+2+f+2.

Note that Vim will not change appearance or indicate that it is pending input for a character sequence, once pressing <Ctrl>+V within <INSERT> mode we are not prompted further. This is expected and if the sequence is done correctly Vim will input the Character specified by the sequence input, whether its decimal, octal, hex, or unicode, just be sure to use the appropriate prefix listed above

Unicode.vim Plugin

The plugin created by https://github.com/chrisbra/unicode.vim on GitHub adds easy support for Unicode characters, some of the useful commands can be seen below (Mostly taken from the official README.md within the plugin repository linked above)

Commands

These commands will be ran within Vim.

If you just installed the plugin, run the below to update your unicode tables, just to be sure you have the full list -

:DownloadUnicode - Download (or update) Unicode data
Searching Unicode Characters
:UnicodeSearch   - Search for specific unicode char
:UnicodeSearch!  - Search for specific unicode char (and add at current cursor position)
:UnicodeName     - Identify character under cursor (like ga command)
Unicode Auto Completion

Unicode.vim supports auto completion using digraphs in vim and unicode table character names.

:Digraphs        - Search for specific digraph char
:UnicodeSearch   - Search for specific unicode char
:UnicodeSearch!  - Search for specific unicode char (and add at current cursor position)
:UnicodeName     - Identify character under cursor (like ga command)
:UnicodeTable    - Print Unicode Table in new window
:DownloadUnicode - Download (or update) Unicode data
:UnicodeCache    - Create cache file
Digraphs / Tables
:Digraphs        - Search for specific digraph char

    :Digraphs

Outputs the digraph list in an easier way to read with coloring of the
digraphs. If a character has several digraphs, all will be shown, separated by
space.

If you want to display a list with a line break after each digraph, use the
bang attribute (Note, this output also contains the name in parentheses). >

    :Digraphs!

And if you want to display all digraphs matching a certain value, you can add
an argument to the command: >

    :Digraphs! A

displays all digraphs, that match 'A' (e.g. all that can be created with the
letter A or whose digraph matches the letter 'A'.)
Note: This is a silly example, that can take some time. You should always be
able to abort that by pressing |CTRL-C|. To output progress information, call
the command with the |:verbose| command modifier.

If you know the name, you can also search for the unicode name: >

    :Digraphs copy

will display all Digraphs, where their unicode name contains the word "copy"
(e.g. copyright symbol). Case is ignored. Note, you need at least to enter 2
characters.

:UnicodeTable    - Print Unicode Table in new window

See the unicode.vim official GitHub docs for more info