For a long time there is Christian music.
Each time has his own signs, the 80's had, the 90's and the music of now too.
I'm sure the CDs who were released in 2009 have a complete different sound than the bands who released their music on cassettes in begin 80's.
What are typical signs of band from the 80's?
What are typical sings for bands from the 90's?
What is typical for the band from now?
What is your favorite time?
What bands do you like from the 80's?
What are your favorite 90's bands?
What are your favorite now bands?