These bindings should work for emacs from 24 upwards.
My emacs config is in my dotfiles.
|Key binding||Name||Purpose||Package||From emacs version|
|C-x SPC||(rectangle-mark-mode)||Select a rectangular region.||None||24.4|
|C-c SPC||(ace-jump mode)||Jump to a letter at start of a word.||ace-jump||unknown|
|C-s C-w||(write-file)||Save current file as a different file||None||unknown|
|C-g C-/||Redo||Redo something you've undone.||None||unknown|
|C-/||Undo||Undo something you've done.||None||unknown|
|C-x k||(kill-buffer)||Close the current buffer.||None||unknown|
|C-x C-f||(find-file)||Visit a file||None||unknown|
|C-x C-v||(find-alternate-file)||Visit a different file||None||unknown|
|C-x C-r||(find-file-read-only)||Visit a file as read-only||None||unknown|
|C-x 4 f||(find-file-other-window)||Visit a file in another window/buffer||None||unknown|
|C-x 5 f||(find-file-other-frame)||Visit a file in a new frame||None||unknown|
|C-a||Jump to start of line||Not emacs specific but IBM home||None||all|
|C-e||Jump to end of line||Not emacs specific but IBM end||None||all|
|C-s M-%||Queried search and replace||None||all|
M-x package-list-packages U xthen follow the prompts
M-xto run any command. e.g
M-x ercto IRC from emacs.