I was trying to find out which web server does Google use to power its websites, but couldn't find any concrete information. Later, Wikipedia article informed that Google's built their own custom Linux based web server that powers all of their major websites, including Google.com. Was wondering what's the logic behind Google customising their own server than going with the ones they have been supporting. They could have gone with Apache, ngix or some other solution. Does anyone know what improvements does Google's server bring over the existing solutions?