Allegro may mean:
The musical tempo meaning "quick and lively" or, literally, "cheerful". See also List of musical terminology.
Allegro library, a computer game programming library
Allegro , a typeface designed in 1936
Allegro MicroSystems, a company based in Worcester, MA that designs and manufactures mixed-signal sensors and IC's
allegro.pl, a Polish online auction website, also known as Aukro (Czech Republic), TeszVesz (Hungary) and Au-Au (Russia and Ukraine)
Allegro , a 1947 musical by Rodgers and Hammerstein
Allegro Common Lisp, a variant of the Common Lisp programming language developed by Franz Inc
Allegro Realty Advisors, a global corporate real estate consultancy based in Cleveland, Ohio
Austin Allegro, a car once manufactured by British Leyland
Name of various parts of a group of keyboard works found in Nannerl's Music Book by Wolfgang Amadeus Mozart (note: the book was originally written by his father Leopold and Wolfgang Amadeus added his works there)
PCB design
Source:
http://en.wikipedia.org/wiki/Allegro