List some UNIX Commands

Answer 1

ls            list files and directories
ls             a            list all files and directories
mkdir            make a directory
cd directory            change to named directory
cd            change to home            directory
cd ~            change to home            directory
cd ..            change to parent directory
pwd            display the path of the current directory

cp file1 file2            copy file1 and call it file2
mv file1 file2            move or rename file1 to file2
rm file            remove a file
rmdir directory            remove a directory

cat file            display a file
more file            display a file a page at a time
head file            display the first few lines of a file
tail file            display the last few lines of a file
grep 'keyword' file            search a file for keywords
wc file            count number of lines/words/characters in file

command > file            redirect standard output to a file
command >> file            append standard output to a file
command < file            redirect standard input from a file
command1 | command2            pipe the output of command1 to the input of command2
cat file1 file2 > file0            concatenate file1 and file2 to file0
sort            sort data
who            list users currently logged in
a2ps             Pprinter textfile            print text file to named printer
lpr             Pprinter psfile            print postscript file to named printer

*            match any number of characters
?            match one character
man command            read the online manual page for a command
whatis command            brief description of a command
apropos keyword            match commands with keyword in their man pages

ls             lag            list access rights for all files
chmod [options] file            change access rights for named file
command &            run command in background
^C            kill the job running in the foreground
^Z            suspend the job running in the foreground
bg            background the suspended job
jobs            list current jobs
fg %1            foreground job number 1
kill %1            kill job number 1
ps            list current processes
kill 26152            kill process number 26152