A pangram (Greek: pan gramma, "every letter"), or holoalphabetic sentence, is a sentence using every letter of the alphabet at least once. Pangrams are used to display typefaces and test equipment. For example, the pangram The quick brown fox jumps over the lazy dog was utilized by Western Union to test Telex/TWX data communication equipment for accuracy and reliability and is now used by a number of computer programs (most notably the font viewer built into Microsoft Windows) to display computer fonts.
Short pangrams tend to be more interesting and more difficult to write because the English language uses some of the same letters (especially vowels) again and again. Longer pangrams may afford more opportunity for humor, cleverness, or thoughtfulness. In a sense, the pangram is the opposite of the lipogram, in which the aim is to omit one or more letters. A perfect pangram in the English language contains every letter of the alphabet only once and can be considered an anagram of the alphabet. These typically are almost meaningless, for example, "Cwm fjord bank glyphs vext quiz".