Linux ABCD....

A             a2p | ac | alias | ar | arch | arp | as | at | awk

B             basename | bash | bc | bdiff | bfs | bg | biff | break | bs | bye

C             cal | calendar | cancel | cat | cc | cd | chdir | checkeq | checknr | chfn | chgrp | chkey | chmod 
               | chown | chsh | cksum | clear | cls | cmp | col | comm | compress | continue | copy | cp | cpio | 
                crontab | csh | csplit | ctags | cu | curl | cut

D             date | dc | dd | df | deroff | dhclient | diff | dig | dircmp | dirname | dmesg | dos2unix | dpost | 
                du

E              echo | ed | edit | egrep | elm | emacs | enable | env | eqn | ex | exit | expand | expr

F              fc | fdisk | fg | fgrep | file | find | findsmb | finger | fmt | fold | for | foreach | fromdos | fsck | 
                ftp

G             getfacl | gprof | grep | groupadd | groupdel | groupmod | gunzip | gview | gvim | gzip

H             halt | hash | hashstat | head | help | history | host | hostid | hostname

I               id | ifconfig | ifdown | ifup | ip | init | isalist

J              jobs | join

K             keylogin | kill | ksh

L              last | ld | ldd | less | lex | link | ln | lo | locate | login | logname | logout | lp | lpadmin | lpc | 
                lpq | lpr | lprm | lpstat | ls

M            mach | mail | mailcompat | mailx | make | man | merge | mesg | mii-tool | mkdir | mkfs | 
                more | mount | mt | mv | myisamchk | mysql

N             nc | neqn | netstat | newalias | newform | newgrp | nice | niscat | nischmod | nischown | 
                nischttl | nisdefaults | nisgrep | nismatch | nispasswd | nistbladm | nmap | nohup | nroff | 
                nslookup

O             on | onintr | optisa

P             pack | pagesize | passwd | paste | pax | pcat | perl | pg | pgrep | pico | pine | ping | pkill | 
               poweroff | pr | priocntl | printf | ps | pvs | pwd

Q             quit

R             rcp | reboot | red | rehash | remsh | repeat | replace | rgview | rgvim | rlogin | rm | rmail | 
               rmdir | rn | route | rpcinfo | rsh | rsync | rview | rvim

S              s2p | sag | sar | scp | screen | script | sdiff | sed | sendmail | set | setenv | setfacl | settime | 
                sftp | sh | shred | shutdown | sleep | slogin | smbclient | sort | spell | split | stat | stop | strip | 
                stty | su | sudo | sysinfo | sysklogd

T              tabs | tac | tail | talk | tar | tbl | tcopy | tcpdump | tee | telinit | telnet | test | time | timex |    
                 todos | top | touch | tput | tr | traceroute | tree | troff | tty

U             ul | umask | unalias | uname | uncompress | unhash | uniq | unmount | unpack | untar | until | 
                unzip | uptime | useradd | userdel | usermod

V             vacation | vedit | vgrind | vi | view | vim | vipw | vmstat

W           w | wait | wc | wget | whereis | which | while| who | whoami | whois | write

X             X | xargs | xfd | xlsfonts | xset | xterm | xrdb

Y             yacc | yes | yppasswd

Z              zcat, zip, zipcloak, zipinfo, zipnote, zipsplit

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