Find character under cursor in vim

Also look at

ga (show character under cursor as ascii)

g8 (show character under cursor as utf8, including Unicode stuff, hex codes etc)

And most usefully:

8g8

Find an illegal UTF-8 byte sequence at or after the
        cursor.  This works in two situations:
        1. when 'encoding' is any 8-bit encoding
        2. when 'encoding' is "utf-8" and 'fileencoding' is
           any 8-bit encoding
        Thus it can be used when editing a file that was
        supposed to be UTF-8 but was read as if it is an 8-bit
        encoding because it contains illegal bytes.
        Does not wrap around the end of the file.
        Note that when the cursor is on an illegal byte or the
        cursor is halfway a multi-byte character the command
        won't move the cursor.

Update

Use Tim Pope’s vim-characterize plugin to get full UNICODE names and data:

In Vim, pressing ga on a character reveals its representation in
decimal, octal, and hex.

Characterize.vim modernizes this with the
following additions:

• Unicode character names: U+00A9 COPYRIGHT SYMBOL
• Vim digraphs (type after to insert the character): Co , cO
• Emoji codes: :copyright:
• HTML entities: ©