What type of music does Philip Glass write?

The style most associate with Philip Glass is minimalism. He is considered to be one of the big names in the school of minimalism, alongside Terry Riley, Steve Reich and others. He has not, however, confined himself to the style, and has worked in Indian music alongside Ravi Shankar and has worked in the film music industry.

To get an idea of his style, I recommend listening to Glassworks, Akhnaten or Koyaanisquatsi. Any of his symphonic or concerto works are also Excellent.