Spell check: underlines instead of highlighting?

[elmerehbi]

I started using spell check in vim recently and they seem to underline instead of highlight. Is that set in your vimrc? And how can I change it to the default / highlighting?

Also I it seems to miss some basic typos (e.g. ompiling for compiling). What might be the source of this?

[alefisico]

I am also interested in this question. Is anybody being able to change this?

[braceletboy]

Firstly, great job on building awesome vim @amix.
Coming to the issue, for me it's not even underlining. Can someone comment on this. I can provide my my_config.vim file if that is necessary.

[amix]

Please see the SpellBad/SpellCap configuration:
E.g.,

SpellBad       xxx ctermbg=9 gui=undercurl guisp=Red