:reg[isters] - show registers content
"xy - yank into register x
"xp - paste contents of register x
"+y - yank into the system clipboard register
"+p - paste from the system clipboard register
NOTE: Registers are stored in ~/.viminfo, and will be loaded again on next restart of vim.
0 - last yank " - unnamed register, last delete or yank % - current file name # - alternate file name * - clipboard contents (X11 primary) + - clipboard contents (X11 clipboard) / - last search pattern : - last command-line . - last inserted text - - last small (less than a line) delete = - expression register _ - black hole register