Celebrating the achievements of women in science, technology, engineering and maths. Ada Lovelace Day Live! 2014. Ada Lovelace Day is an international celebration of the achievements of women in science, technology, engineering and maths (STEM). Grassroots events and activities are held all around the world and, every year since 2010, we've put on our own flagship event in London featuring presentations by and stories of inspiring women in STEM.