The quick brown fox jumps over the lazy dog.
That's the classic English pangram (sentence containing all 26 letters), one of few useful sentences I learned as a young kid and still remember, along with pneumonic devices "She made Harry eat onions" (the Great Lakes, west to east) and "Every good boy does fine" (treble scale).
The lazy dog sentence as far as I know arose out of a need to quickly test for stuck typewriter keys. The need to do anything efficiently (or at all) with a typewriter has gone completely obsolete, but pangrams are still good for trying out fonts, and for amusing word nerds such as myself.
I discovered the discotheque one in a photo app and then realized this was a thing beyond typewriters and typefaces, that people sit around coming up with them, and the sheer number of them far outpaces their usefulness. I am not that much of a word nerd. The 26 letter ("perfect") pangrams are pretty much cheaters (examples: "Zombies play crwth, quj FDG xvnk" and "Jump dogs, why vex Fritz Blank QC?") insofar as you would define a sentence as loosely as: a thought that anyone sane would find a reason to utter out loud.
Once you allow some extra letters to sneak in though, you get some gems like:
Junk MTV quiz graced by fox whelps.
Both fickle dwarves jinx my pig quiz.
Jack, love my big wad of sphinx quartz!
Five quacking zephyrs jolt my wax bed.
Pack my box with five dozen liquor jugs.
Fix problem quickly with galvanized jets.
When zombies arrive, quickly fax Judge Pat.
Watch "Jeopardy!", Alex Trebek's fun TV quiz game.
Foxy diva Jennifer Lopez wasn't baking my quiche.
Cozy lummox gives smart squid who asks for job pen.
Six big devils from Japan quickly forgot how to waltz.
.... all brilliant, I know, but the clear winner is:
"Who am taking the ebonics quiz?", the prof jovially axed.
Read it and weep.
main source: http://clagnut.com/blog/2380/