MacTutor - a nice ressource for Mathematic enthusiasts ( mathshistory.st-andrews.ac.uk )

MacTutor is a free online resource containing biographies of more than 3000 mathematicians and over 2000 pages of essays and supporting materials.

MacTutor is constantly expanding and developing.

MacTutor was created and is maintained by Edmund Robertson and John O'Connor of the School of Mathematics and Statistics at the University of St Andrews, and is hosted by the University
Their contributions to the history of mathematics have been recognised by Numerous Awards including the Hirst Prize of the London Mathematical Society in 2015.