Claim: George R. R. Martin is also referred to by a nickname.

-RCB- -RCB-   George Raymond Richard Martin -LRB- born George Raymond Martin ; September 20 , 1948 -RRB- , often referred to as GRRM , is an American novelist and short-story writer in the fantasy , horror , and science fiction genres , screenwriter , and television producer . He is best known for his international bestselling series of epic fantasy novels , A Song of Ice and Fire , which was later adapted into the HBO dramatic series Game of Thrones .   Martin serves as the series ' co-executive producer , and also scripted four episodes of the series . In 2005 , Lev Grossman of Time called Martin `` the American Tolkien '' , and the magazine later named him one of the `` 2011 Time 100 '' , a list of the `` most influential people in the world . ''