Sierra is an American video game publisher started in 1979. They are based in Oakhurst California and later in Fresno California. Sierra is best known for there graphic adventure games started in 1980.Sierra was first founded by Ken Williams and Roberta Williams since then they have produced text advanture games in the early years 1980-1990. In the 2000s they worked with Midway Austin and produced The Hobbit.
In 2005 they added an online to there games.
In 2007 they released real time tactical games.
Later in 2014 they added a new logo.
https://en.m.wikipedia.org/wiki/Sierra_Entertainment (info + image)