linux commands

aliasallows you to set aliases and view the current aliases
awksearch for a pattern within a file.
badblockssearches a device for bad blocks.
bgmove a job running in the foreground to the background.
bzip2used to compress and decompress files. Similar to gzip.
chattrchanges the attributes of a file or folder.
chrootchange the root directory for a command.
chmodused to change permissions on a directory or file.
chownused to change the owner of a file or directory.
chgrpused to change the group a file belongs to.
clearclears the screen
cpiocopies file.
catdisplays the content of a file
cdchanges directories.
cronused to execute commands at a certain time.
crontaballows you to view or edit the current cron jobs.
dateprints current date to the screen
dulists disk usage in a directory.
dfreports disk usage information. df -h
edquotasets quotas for specific users.
envlists current environment variables.
fdiskused to create/edit/delete partitions.
fsckchecks a file system for consistency.
fgused to send jobs to the background.
fuserchecks to see what processes and users have open files.
findsearches for a file.
freewill show total memory, used memory, and free memory.
gpasswdused to set a password for a group.
grepused to search through a file for a specified pattern.
gunzipuncompress files compressed by gzip.
headdisplays the first 10 lines of a file to the screen.
hdparmgets disk information.
historylists recently executed commands.
hostused to get DNS info.
iddisplay information about yourself or another user.
jobsused to show jobs running in the background.
joinjoin lines of two sorted.
killused to kill a process.
killallkill processes by command name.
kernelcfga graphical application configures Linux.
klogdcontrol which kernel messages.
linuxconfcommand line GUI which lets you configure your linux
lsdisplays a directories contents.
lnused to create hard and symbolic links.
lessdisplay the contents of a file
lddshows what shared libraries a program is dependent on.
ldconfigused to configure/view shared libraries.
lastlists logins and reboots.
lastlogprint the last login times for system accounts.
lsmodlists loaded modules.
lsattrlists the attributes for a file or folder.
mountused by itself, reports the currently mounted files.
modinfogive info about the module.
modprobequeries modules.
mandisplays the Man page for a given command.
mkdirmake directory
mergemerge multiple files together.
morelets you page through text one screen full at a time.
niceused to set process priorities.
nslookupused to get DNS info from name servers.
netstatshows active sockets.
psdisplays current processes
pingused to test connectivity between two hosts.
pwdpresent Working Directory
rmdirremove directory
rpcinfoused to see what rpc services are available.
routeused to view/change routes between you and other hosts.
smbclientused to connect to Windows shares or Samba.
smbaddusermaps linux user names to Windows NT user names.
smbpasswdused to update the smbpasswd file with new accounts.
setused to read and write variables.
setquotaused to set disk quotas.
sortsorts lines in a file by alphabetical order.
suchange to Super User (root).
shutdownshutdown machine
showmountshows mount information for an NFS server.
swaponturns on the swapfile.
swapoffturns off the swapfile.
testparmused to troubleshoot Samba.
tarused to compress multiple files.
tacview a file from the last line up.
touchcreates an empty file.
taildisplays the last 10 lines of a file to the screen.
trconverts one set of characters to another.
tracerouteused to track the path a packet takes to a host.
topshows information about the most CPU-intensive Apps.
umountremoves a device from the filesystem.
unamedetermines OS name, version and machine name.
vmstatlists information on memory usage.
whereisfinds documentation files.
whotells you who is logged into your server.
whoamitells you your user information.
wcprint the number of bytes, words, and lines in files
whichfinds the full path for a command.
zcatread files that have been compressed with gzip.