Four legendary women in IT

As we approach International Women’s Day, we took time to put together the stories of four ladies, who made a significant contribution to the development of information technology.

Ada Lovelace

(10 December, 1815 – 27 November, 1852)

An English mathematician, the daughter of the poet George Gordon Byron and the first computer programmer. Ada had been particularly inclined to math since childhood. Among her teachers were the famous mathematicians Augustus de Morgan and Mary Somerville. The latter introduced Ada to Charles Babbage, a professor at Cambridge University. Babbage worked on creating a so-called difference engine that produced mathematical calculations with a capacity of twenty decimals. ‘Charles Babbage’s Big difference Engine’ is considered to be the very first computer, although its construction was completed only after Babbage’s death. Ada helped Babbage to describe his machine and took part in the interpretation of his work. Some of her notes, for instance, include a method for calculating a sequence of Bernoulli numbers with the Engine. Today this method is considered to be the world’s first computer program, which is why Lovelace is now widely recognized as the first computer programmer.

While Babbage simply strived to create a machine that would be effective in calculating mathematical tables, Ada considered it in a more abstract way. She was thinking about the big picture – and, as a result, invented the concept of universal computing.

Ada also introduced the terms ‘working cell’ and ‘cycle’.

In 1980 the United States Department of Defense approved the computer language Ada, designed for embedded systems and named after Ada Lovelace.

Hedy Lamarr

(November 9, 1914 – January 19, 2000)

An Austrian-born American film actress, who appeared in 55 movies and is known for the invention of a radio guidance system. She has also received worldwide fame after the film ‘Ecstasy’ – the first motion picture to include a nude scene: for 10 minutes Hedy Lamarr is seen swimming nude in a lake.

Lamarr used to be married to Friedrich Mandl, an Austrian military arms manufacturer and millionaire. Mandl supported Austrofascism and negotiated the supply of weapons to Nazi Germany. Hedy Lamarr did not share her husband’s political beliefs, so one day she fled from him after drugging her maid with some sleeping pills.

On September 17, 1940 a British steam evacuee ship was torpedoed by Germans and sunk. 77 children died as a result. This became the impetus to a new inventive activity for the non-technical actress.

Lamarr used to be present at her husband’s business meetings. From those, she knew how radio-controlled torpedoes worked, and was able to reproduce the technical details. Lamarr discovered that if the target’s coordinates were transmitted to the torpedo at a constant frequency, the enemy could intercept the signal, kill or even redirect the torpedo. Lamarr suggested sending a part of the signal at one frequency and then switching to another frequency to transmit the next part of the signal.

If the transmitter and receiver are matched for frequency hopping, it would be something like a piano four-hands, and the signal could become resistant to jamming. She also assumed that the mechanical matching of the transmitter to the receiver could take place by means of a medium similar to a mechanical piano roll. The roll with pins and a drive from a chronometer seemed small enough to fit in the body of the marine torpedo. According to Lamarr, the system could use a set of 88 radio frequencies – which is also the standard number of piano keys.

Together with her friend, George Antheil, an American avant-garde composer, Hedy Lamarr started working on the torpedo that would be impossible to intercept or kill.

On August 1942 they received a patent # 2,292,387 for their ‘Secret Communication System’. The patent described secret communication systems, including the transmission of false channels at different frequencies.

Hedy Lamarr’s work became the basis for nowadays spread spectrum communication technologies such as CDMA, Wi-Fi and Bluetooth.

Karen Spärck Jones

(26 August, 1935 – 4 April, 2007)

British computer scientist, Professor Emerita of Cambridge University.

Karen Spärck Jones created the concept of inverse document frequency (IDF), which is nowadays used by many search engines as a part of the tf-idf weighting scheme. Thanks to Spärck Jones, we are able to use words in our search queries, instead of equations and code.

Her work focused on the use of a thesaurus for speech and information processing. Groups of words and their synonyms were transferred onto the punched cards, and then used to develop more complex ways of finding the difference between polysemantic terms. One of her examples – “The farmer cultivates the field” – showed that though the word “field” has a range of meanings from “land” to “subject”, adding a general underlying concept such as “Agriculture”, which applies to “farmer”, “cultivate” and “field”, would select “land” as the intended meaning.

My slogan is: ‘Computing is too important to be left to men’,” she said. “I think women bring a different perspective to computing; they are more thoughtful and less inclined to go straight for technical fixes. My belief is that, intellectually, computer science is fascinating – you’re trying to make things that don’t exist.

In 2008, in order to commemorate her achievements, the British Computer Society created an annual Karen Spärck Jones Award, sponsored by Microsoft Research.

Radia Joy Perlman

Born January 1, 1951

An American software designer and network engineer, a professor at Harvard University and the University of Washington, ‘Mother of the Internet’.

While studying at the Massachusetts Institute of Technology (MIT), Radia Perlman developed a child-friendly version of the educational robotics language LOGO, called TORTIS. During research performed by MIT Artificial Intelligence Laboratory, young children of 3½ years and more programmed an educational robot called a Turtle using Perlman’s language. Because if that, she has become ‘a pioneer of teaching young children computer programming’.

Perlman is famous for her invention of the Spanning Tree Protocol (STP). Its basic function is to prevent bridge loops in the Ethernet network by eliminating redundant links or paths.


Perlman has been called the ‘Mother of the Internet”, because the STP protocol allowed the Ethernet to handle massive networks. But here’s what she has to say about it:

The Internet was not invented by any individual. There are lots of people who like to take credit for it, and it drives them crazy when anyone other than them seems to want credit, so it seems best to just stay out of their way.

Perlman owns over 100 patents related to encryption and routing.