The ABC's of Unix

    A is for Awk, which runs like a snail, and
    B is for Biff, which reads all your mail.
    C is for CC, as hackers recall, while
    D is for DD, the command that does all.
    E is for Emacs, which rebinds your keys, and
    F is for Fsck, which rebuilds your trees.
    G is for Grep, a clever detective, while
    H is for Halt, which may seem defective.
    I is for Indent, which rarely amuses, and
    J is for Join, which nobody uses.
    K is for Kill, which makes you the boss, while
    L is for Lex, which is missing from DOS.

    M is for More, from which Less was begot, and
    N is for Nice, which it really is not.
    O is for Od, which prints out things nice, while
    P is for Passwd, which reads in strings twice.
    Q is for Quota, a Berkeley-type fable, and
    R is for Ranlib, for sorting ar [sic] table.
    S is for Spell, which attempts to belittle, while
    T is for True, which does very little.
    U is for Uniq, which is used after Sort, and
    V is for Vi, which is hard to abort.
    W is for Whoami, which tells you your name, while
    X is, well, X, of dubious fame.
    Y is for Yes, which makes an impression, and
    Z is for Zcat, which handles compression.