Along with old-time, Country Gospel is the oldest genre in country music. Though it somewhat changed with the times, country gospel remained the most simple and straightforward of all country subgenres. The sound of country gospel is similar to traditional country -- the only difference is, the subject matter is religious, not secular. Like traditional country, the sound of country gospel became smoother and more pop-oriented as the decades progressed, and by the early '70s, it became nearly indistinguishable from the lush sounds of mainstream pop. That trend continued throughout the rest of the '70s and '80s, and by the '90s, contemporary country gospel sounded identical to the adult contemporary inclinations of CCM.