Linux is a free, open-source operating system that provides functionality similar to Unix systems. The document then lists and describes several common Linux commands used to navigate directories, view files and system information, manage processes, and edit text files. It also includes a diagram of the standard Linux directory structure and brief descriptions of the purpose of each top-level directory.

1. Linux is a Unix-like operating system that was designed to provide personal computer users a free or very low-cost operating system comparable to traditional and usually more expensive Unix systems. Linux has a reputation as a very efficient and fast-performing system.

2. LINUX COMMANDS These few commands will: a) Tell us where we are, b) take us somewhere else, and c) show us what's there. 1)pwd -“Print Working Directory”. Shows the current location in the directory tree. Eg:fp088@pbs088:~$ pwd /home/fp088 2)cd-“Change Directory”. When typed all by itself, it returns you to your home directory. Eg:fp088@pbs088:~$ cd fp088@pbs088:~$ 3)cd directory-Change into the specified directory name. Eg: cd /usr/src/linux

3. 4)ls-List all files in the current directory, in column format. Eg:fp088@pbs088:~$ ls Desktop Downloads Music Public Videos Documents examples.desktop Pictures Templates 5)clear-Clear the terminal screen 6)touch-Create empty file of zero byte Eg: fp088@pbs088:~$ touch aa 7)rm-Delete a file. Eg: fp088@pbs088:~$ rm aa 8)which-Shows the full path of shell commands found in our path Eg:fp088@pbs088:~$ which grep /bin/grep

4. 9)locate-A quick way to search for files anywhere on the filesystem. 10)ps-Lists currently running process (programs). Eg:fp088@pbs088:~$ ps PID TTY TIME CMD 1797 pts/0 00:00:00 bash 2336 pts/0 00:00:00 ps 11)w-Show who is logged on and what they are doing. Eg:fp088@pbs088:~$ w 11:05:22 up 1:32, 2 users, load average: 0.01, 0.02, 0.01 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT fp088 tty7 :0 09:33 ? 3:58 0.19s gnome-session fp088 pts/0 :0.0 09:35 0.00s 0.27s 0.01s w 12)id-Print your user-id and group id's Eg:$ id uid=1000(fp088) gid=1000(fp088) groups=4(adm),20(dialout),24(cdrom),46(plugdev),104(lpadmin),115(admin),120(sambashare),1000(fp088)

5. 13)df-Report filesystem disk space usage. Eg:~$ df Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 73742752 2729736 67267064 4% / udev 997964 208 997756 1% /dev none 997964 1540 996424 1% /dev/shm none 997964 88 997876 1% /var/run none 997964 0 997964 0% /var/lock none 997964 0 997964 0% /lib/init/rw 14)echo-Display text on the screen. Eg:echo "hello World" hello World 15)date-date to set your server's date and time 16)finger-Use finger to see who's on the system Eg:~$ finger Login Name Tty Idle Login Time Office Office Phone fp088 fp088 tty7 May 20 09:33 (:0) fp088 fp088 pts/0 May 20 09:35 (:0.0)

6. 17)cal-displays a calendar Eg:$ cal May 2010 Su Mo Tu We Th Fr Sa 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 18)ls -al List all files in the current working directory in long listing format showing permissions, ownership, size, and time and date stamp 19)more-Allows file contents or piped output to be sent to the screen one page at a time. <ls -al |more> 20)mv-Move or rename files mv -i myfile yourfile Move the file from &quot;myfile&quot; to &quot;yourfile&quot;. This effectively changes the name of &quot;myfile&quot; to &quot;yourfile&quot;. 21)shutdown -Shuts the system down. <shutdown -h now> Shuts the system down to halt immediately.

7. 22)whereis-Show where the binary, source and manual page files are for a command <whereis ls> Locates binaries and manual pages for the ls command. Eg:~$ whereis ls ls: /bin/ls /usr/share/man/man1/ls.1.gz fp088@pbs088:~$

8. cooledit - a pretty powerful GUI text editor

9. jed - has pretty good emacs emulation (it can even read mail like emacs!). It does simple syntax highlighting for TeX files, including giving positioning of parentheses.

10. It would seem to be pretty configurable and takes up much less disk space than emacs, although more than joe and muemacs. It works well in console mode, and still manages to use colors for menu bars and syntax highlighting.

11. The program xjed which comes with some versions starts up its own X terminal when invoked. Editors

12. joe - &quot;Joe's Own Editor&quot;, a fairly powerful editor with a compact binary and an ability to emulate Wordstar, Emacs, Pico, and a few other editors.