Explaining Megabytes, Kilobits and Megahertz in Computers
It gets a bit confusing to the layman when confronted with Megabytes and Terabytes and other terms when trying to decide on what computer to buy.
A Mega What?
A byte is the amount of computer memory needed to store a piece of data the size of one character, such as an “A.” So if you wanted to store the word “cool” on your computer, this would take up 4 bytes of space.
A Kilobyte, which is a thousand bytes, is equivalent to about half a page of typed text.
A megabyte is one million bytes, so you could store the text of quite a thick best selling novel in this much memory. A Megabyte is actually 2 to the power of 20, which is 1,048,576. You may see this figure reflected at times when checking sizes of files, and it can get a bit confusing when trying to figure out the exact size of a hard drive.
A Gigabyte is a thousand million bytes, equivalent to a thousand novels, and a Terabyte can hold a million novels. A gigabyte is precisely 2 to the power of 30, which is 1,073,741,824 bytes.
Text uses relatively little memory. Photographs, movies and music tracks tend to use a lot more. A photograph will usually use a couple of megabytes, a music track a similar amount, and a movie can use up to a gigabyte or two, since a movie consists of a stream of photographs, usually displayed at the rate of 25 photos per second or more.
How Memory Works.
Memory is really simple. It’s just a huge bunch of electronic switches. Each switch is either on or off. Each “switch” is called a bit. 8 of these bits constitute a byte. These 8 bits form a code, which the computer translates into text, graphics, music, etc. For example, the letter “J” in memory is held by the code 1001011, where 1 means the switch is on, and 0 means it’s off. Each megabyte consists of about 8 million of these microscopic switches.
Hard Drive space is also referred to as memory, but it works a little differently, in that the bits are stored on it magnetically and not as a switch, but these bits are always transferred to the “switch” type of memory, known as RAM (Random Access Memory) before the computer actually uses it.
The speed of a computer is measured in Megahertz, which is a measure of how many times a second computer operations can be done. A computer that runs at 2.8GHz can do operations at the rate of 2800 million times per second. That’s pretty fast.
RAM, the memory, usually has it’s own speed rating, which is slower than the main computer speed. This is because the main computer has to tell the memory when to send data and when to stop, and at the same time it has to do other stuff like calculate using this data, so it needs the higher speed.
The amazing thing about computers is the incredible speed that everything takes place at. The fact that this speed is increasing all the time is even more mind boggling.
The future sure is going to be interesting!