There are two types of Hardware components. Hardware saves almost everything on your computer, including photos, music, applications and docments. One is called a Hardrive and it is a big component with a disc and a arm inside. If dropped the arm, which reads the disc can be moved if dropped and therefore skipping memory. The other is an SSD (SolidStateDrive). It is smaller and does not have a moving part so it is harder to break and will not skip any memory. It is much thinner aswell so it can be used in smaller computer such as the Mac Book Air.
Optical Drives are the Drives that you put Dvds, Software and more lately BlueRays. They read the disc with a laser. You find these in most computers and playstation/Xbox. On the more thin computers like the Mac Book Air, it will not hold and optical drive as they are usually quite thick.
Monitors are the things that you use to see and contol you computor. Without a monitor you will not be able to do any thing. The new Version on displays are retina/high definition, which are much higher quality that the normal quality monitors. Retina displays are used in the latest ipods, iphones, tabs and apple have introduced it to thier mac books
CPu stands for core processing unit. It is used in all computers and phones. It makes your computer process every thing at lightning speed, it is the brain of the computer. Without it your computer would not work. It is Measured in GigaHertz (GHz). There are different types of processors. There is a Single, Dual and Quad. If you have a Quad processor it doesnt make your computer faster it just will process 4 things at once.
RAM stands for random acces memory and it is the temporary memory that can hold things on the quick acces on your desktop. It also holds things in your clipboard (copy and paste). The more RAM you have the more things you can have up on your desktop and the more RAM your computer has it is faster when handeling more windows and is less likely to crash you computer. Its is usually called memory.