Okay kiddo, so progressive rock is a kind of music that was popular in the 1970s and it was all about making really complex and interesting music.
In the beginning of the 1970s, bands like King Crimson and Yes were doing really cool things with their music. They would use unusual instruments, like the mellotron and the synthesizer, to create sounds that had never been heard before. They also wrote songs that were really long and had lots of different parts to them, like a story with lots of chapters.
As the decade went on, more and more bands got into progressive rock. Some of the most popular ones were Pink Floyd, Genesis, and Rush. They all had their own unique sound and style, but they all shared a love of making music that was really different and interesting.
One of the most famous progressive rock albums of all time was Pink Floyd's "Dark Side of the Moon." It was released in 1973 and it was a huge hit. It's still really popular today, and lots of people think it's one of the best albums ever made.
Towards the end of the 1970s, punk rock started to become really popular. Punk was very different from progressive rock - it was much simpler and more raw. Some people thought that progressive rock was too complicated and pretentious, and they started to turn away from it.
But even though progressive rock wasn't as popular by the end of the decade, it still had a big impact on music. Lots of bands that came after the 1970s were influenced by progressive rock, and you can still hear its influence in some of the music we listen to today.