Mega, giga and tera are used to express speeds of networks and storage capacities on computers. The terms mean the same thing in regular life in various measurements.

Mega is the expression is a million although when used in computers each of these terms is an approximation of the exact number the computer is using as the computer works in powers of two and these are from powers of 10. If your Internet connection is one mega bits per second or one meg it is 1 million bits per second

Giga is a billion so if your Internet connection is one giga bit per second or one gig it is one billion bits per second. If you have a 500 gigabyte hard drive you can store 500 billion bytes (or characters) on it.

Tera is a trillion or a thousand billion (what the US debt is in dollars) so if you have a two terabyte hard drive you can store 2 trillion bytes (or characters) on it.

Exa is a million tera or one quintillion. Google measures the amount of storage they have in exabytes.

Peta is somewhere in the future, but I suspect sooner than we suspect for personal devices. It is a quadrillion or a thousand tera.

Some of you may remember when we measured speeds in kilobits (or thousands of bits per second). Some people still use this as some are still on dial-up.

Mega is a million which is what most peoples Internet speeds are measured in. Some may remember back to about 1982 when the first hard drives came out for PCs they were 5 megabye drives. We were in a text computer world then. The question then was what would you ever use 5 megabytes for. Today, just over 30 years later, you cannot get one picture off your camera on a 5 megabyte hard drive.