There are a lot of computers in the world and most of them have Hard Disk Drives (HDD) which are spinning disks that have magnetic patterns on them and a head that reads them. The head goes around the HDD VERY fast and gives you ok response times. They spin at 7-10,000 RPM and are not very drop resistant at all. They don’t like being touched or moved as they are quite delicate.
A few computers (mainly gaming and servers) have a Solid State Drive (SSD) and they are much faster than hard drives but not as reliable and can degrade over time. Hard drives are a lot bigger than an SSD and will not survive a big drop, while SSD’s can. For a gaming computer, you should probably get an SSD to store all your games and OS and a hard drive to store your music, movies or big files. An SSD will be a lot cheaper than a hard drive.