A is for awk which is awkward to run
B is for bash which makes computing fun.

C is for language of hackers' own, while
D is for df where disk mounts are shown

E is for emacs to edit with ease and
F is for fsck which rebuilds the trees

G is for grep where text will be found and
H is for halt that will run system down

I is for indent which rarely amuses, and
J is for join which nobody uses.

K is for kill which stops your process while
L is for ls and shows what you posess

M is for move which will your files alter;
N is for nice which is used when things falter

O is for od which prints out things nice, while
P is for passwd which reads in strings twice.

Q is for quota to set for every dude and
R is for rm to remove files for good

S is for su which as root you sets while
T is for tar which archives begets

U is for uname which tells system name, and
V is for vi which is woefully lame.

W is for who which tells you who's logged on, while
X is, yup, X, which gets windowing done

Y is for yes which makes an impression, and
Z is for zcat which handles compression.