Session When you start Emacs, package Session restores various variables (e.g., input histories) from your last session. It also provides a menu containing recently changed/visited files and restores the places (e.g., point) of such a file when you revisit it.
recentf recentf.el maintains a menu for visiting files that were operated on recently. When enabled a new "Open Recent" submenu is displayed in the "Files" menu. The recent files list is automatically saved across Emacs sessions.
tramp TRAMP stands for `Transparent Remote (file) Access, Multiple Protocol'. This package provides remote file editing, similar to ange-ftp and EFS. The difference is that ange-ftp uses FTP to transfer files between the local and the remote host, whereas TRAMP uses a combination of rsh and rcp or other work-alike programs, such as ssh/scp.
cua CUA-mode is a complete replacement for the pc-select, delete-selection, and s-region packages, with one important improvement: it (almost) transparently allows you to use the C-z, C-x, C-c, and C-v keys as you are accustomed to on systems like Windows. You can also use the CUA enhancements without rebinding the C-z, C-x, C-c, and C-v keys if you activate it using (CUA-mode 'emacs).
folding This programs makes it possible for Emacs to hide irrelevant sections of code or text. When a folded text is loaded, only the top headers are visible. The contents of a fold can be made either visible in the surrounding context (opened), or on it's own (entered).
indent-region, align-regexp, dabbrev-expand, toggle-read-only,
goto-line, comment-region, imenu, zap-up-to-char
(check the docs for further information)
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