Okay kiddo, so imagine you have two favorite cartoons that you really like to watch: Ninja Turtles and Power Rangers. You want to watch them whenever you want, but you don't have a lot of money to buy all the episodes on DVDs or download them from the internet. So you go to the store and ask for a tape to record them.
A long time ago, there were two types of tapes that people used to record their favorite TV shows: VHS and Betamax. They looked like big black rectangles that you stick them in a video player that connected to your TV. These tapes worked just like recording something from the TV onto a DVR or a USB drive today.
Now, the problem was that Ninja Turtles and Power Rangers were owned by different companies that wanted their show to be watched on a specific tape format. Some companies supported VHS and others supported Betamax. The people who made VHS machines and tapes wanted you to choose their format, and the people who made Betamax machines and tapes wanted you to choose theirs.
So, there was a videotape format war going on, just like two teams of superheroes fighting for attention. People who didn't care about which format was better just wanted to watch their shows without any issues. But, if you chose one format over the other, sometimes you wouldn't be able to watch some cartoons because they were only available on the other format.
It was like having only Ninja Turtles on VHS and Power Rangers only in Betamax. Some people chose to buy both types of machines and tapes, but not everyone could afford it.
Eventually, VHS won the videotape format war because they were cheaper to produce and could record for longer periods. Betamax was discontinued, and people who supported it had to switch to VHS if they wanted to keep watching their shows.
So, now that you understand the concept of videotape format war, it's like having two teams competing for your attention, and you have to choose which one you want to be a fan of, but sometimes you miss out on things if you choose the wrong team.