Programmer's Almanac: Dec 10, 2006

On this day in 1815, Ada Lovelace, the Countess of Lovelace, daughter of Lord Byron, was born. If Grace Hopper (see December 9th) was the Mother of all Programmers, then Ada is definitely the Grandmother of all Programmers.

Ada, a mathematician, is credited with being the first programmer ever. She exchanged letters with Charles Babbage, who built (but rarely completed) complex computing machines, called Engines, using wooden gears. The most famous of Babbage's engines was known as the Analytical engine, and would have featured input using punched cards and even a printer. Ada wrote a program for the engine that would have calculated Bernoulli numbers, which are important for Number Theory.

Although Babbage never completed his Analytical Engine due to lack of funding, a replica of another of Babbage's machines was built from the original plans. It would have worked.

Ada is also the name of a computer language, named after the Countess. Starting in 1975, Ada was developed by the United States Department of Defense, with the goal of a common language for all U.S. military systems, from airplanes to tanks to radars. At that time, the Department and its contractors were using over 450 different computer languages for embedded military systems.

The Ada language features extremely strong type checking and validation capabilities which were hoped to provide high-reliability and maintainability. Today, even commercial systems that we depend on for our safety, such as aviation and railroad control are written Ada.

The hello world program for Ada looks like this:

 -- Hello World in Ada

with Text_IO;
procedure Hello_World is

begin
Text_IO.Put_Line("Hello World!");
end Hello_World;

One of the first success stories using Ada was the BSY-2, an embedded system for Submarine combat. Comprising 3.1 million unique lines of code, it is one of the largest embedded systems programs ever written.

(c) 2006, Jorge Monasterio