What is RAM and why do we need it?

So what is RAM?

Ram is a form of computer data storage. It stands for Random Access memory.For example, a computer with 8MB RAM has approximately 8 million bytes of memory that programs can use. In contrast, ROM (read-only memory) refers to special memory used to store programs that boot the computer and perform diagnostics. Most personal computers have a small amount of ROM (a few thousand bytes). In fact, both types of memory (ROM and RAM) allow random access.

However, RAM acts quite differently from a hard drive's memory. The primary difference between RAM and hard drive memory is that RAM is temporary. Information that gets written and retrieved from RAM is wiped out when you shut down your computer, in contrast to a hard drive's memory which stores the information in-between boots. There are different types of RAM , for example SRAM, Static random access memory is used primarily for cache. And DRAM Dynamic random access memory. Below is a link to the source of the picture and more info.

Why do we need it?

Most data is stored on the computers hard disk drive, but it can be quite slow to retrieve data from the hard drive. RAM, however is very quick when it comes to retrieving data, so the computer transfers programs and files into the RAM when they are in use. The price range varies from around £20 to over £650 depending on how big you want it.