So Google made that logo for the world to know that on this day, it's Nikola Tesla's birthday! According to Wiki, Tesla was an inventor and a mechanical and electrical engineer.So let me just quote this from Wiki. I think this is the most important:
Tesla is often described as an important scientist and inventor of the modern age, a man who "shed light over the face of Earth". He is best known for many revolutionary contributions in the field of electricity and magnetism in the late 19th and early 20th centuries.Happy birthday Mr. Tesla. Job well done! *wink.