Command Description DOS equivalent
ls lists the content of a directory dir
cd change directory cd
cd .. parent directory cd..
mkdir creates a new directory md
rmdir eliminates a directory deltree
cp copy a file copy, xcopy
mv moves a file move
rm removes a file del
passwd changes the user's password  
cat displays the file's content type
more displays the file's content with pauses type |more
man

apropos

help for the requested command help
lpr prints the requested file print
chmod changes the attribute of a file

chmod XXX file

XXX= User|Group|Other where X represents an integer 1<X<7


Read=4, Write=2, Run=1
X=Read+Write+Run
0 means no rights
1 means running right
2 means writing right
3 means writing and running rights
4 means reading right
5 means reading and running rights
6 means reading and writing rights
7 means all rights
 
chfn changes the personal information viewed with finger  
chsh changes the shell: chsh user emplacement_du_shell  
finger lists online users  
traceroute traces the route between the local and distant machine  
ftp [machine] [port]

get

put

quit

transfers the file betwee the local machine and the target machine

recovers a file

sends a file

quits the FTP session

 
telnet [machine] performs a telnet  
talk allows to talk to a connected user

talk user

 
mesg authorizes or rejects the talk command

mesg n : Starts receiving talk messages

mesg y: Allows the receipt of talk messages

 
logout disconnection  

Table of content for the example was taken from the http://en.kioskea.net.