Blue Jeans usually means jeans, which are denim trousers.
Jeans are trousers, a type of garment, typically made from denim or
dungaree cloth. Often the term "jeans" refers to a particular style of
pants, called "blue jeans," which were invented by Jacob W. Davis in
Levi Strauss & Co. in 1871 and patented by Jacob W. Davis and Levi
Strauss on May 20, 1873. Prior to the Levi Strauss patented trousers,
the term "blue jeans" had been long in use for various garments
(including trousers, overalls, and coats), constructed from blue colored
denim. Originally designed for cowboys and miners, jeans became popular
in the 1950s among teenagers.
However, blue jeans transcend simple pants because they can inspire
so much more.