If you use VIM to write code or text documents then it is useful to know that VIM has an auto spell check feature and it will highlight word typos in red for the language while you type and also highlights any uncapitalised in blue. VIM is also smart enough to only spell check comments and string literals when it detects a code. Syntax highlighting must be enabled and available for programming language for it to work.

This feature is available only in VIM versions 7+ and can be enabled and disabled by using below commands respectively in command mode,

:set spell
:set nospell

To enable spell checking automatically, place set spell in your ~/.vimrc file.

By default spell checking is enabled for en, to enable spell checking for a different language or region specific English use,

:set spell spelllang=<language>
:set spell spelllang=en_us

To navigate to the highlighted words, get a list of possible suggestions and fix mistakes use below commands in escape mode,

• [s - Move to the next misspelled word after cursor.
• ]s - Move to the previous misspelled word before cursor.
• z= - For a word under a cursor, suggest correct spelling or an alternative. This works for non highlighted words as well. A list of possible suggestions are listed and choose a number to pick a word from the suggestion. To not pick any words press enter without a number. If used with a count in the beginning like 1z= it will pick the word at count automatically.
• spellr[epall] - Repeat the replacement done by z= for all matches in current window.
• zg - Add word under the cursor as a good word to ‘spellfile’
• zw - Will mark a word as incorrect and add it to the ‘spellfile’
• zug/zuw - Undo the respective commands, removes the word from the entry in ‘spellfile’

For more details refer VIM documentation using,

:help spell - For info page about spell checking
:help z=    - For help about z= command.

References:

1. VIM info pages - :help [name]
2. RIP Tutorial - VIM - Spell Checking
3. linuxhint.com - VIM Spell Check