Ada Lovelace was the world's first computer programmer - writing the first algorithm for Charles Babbage's Analytical engine.
Since 2009 her achievements have been remembered and used to help promote the many and varied roles of women in STEM.
So to mark the day - here's a run down of some of the science and technology stories we've featured over the last year.
In no particular order:
Source : https://www.itv.com/news/anglia/2018-10-09/happy-ada-lovelace-day-a-look-back-at-women-in-stem/