In Quick Man Pages, I introduced K which shells
out to the man page for the unix command under the cursor. It gets better
though. Vim has a built-in plugin, man.vim, that you can enable which
allows you to view man pages without shelling out.
Add the following to your .vimrc file
runtime! ftplugin/man.vim
" grep
Then save it and re-source the configuration with :source %.
With the man.vim plugin enabled, you can now move your cursor over the
word grep and hit <leader>K which will pop open the man page for grep
in a unnamed, split buffer.
Not only does this prevent context-switching when viewing a man page, but it also gives you the full power of vim over the content of the man page. You can search, you can yank text, or you can even pop open the man page for another command.
See :h ft-man-plugin for more details.