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Gigabytes? Terabytes?A long entry in Ken’s Corner: Gigabytes? Terabytes?

Some terms are so common in the computer world, people in the business take for granted everyone will know what they mean. Of course, that’s rarely correct and some of those terms are confusing as heck.

One of those is the byte; what is it and how many do I need? What’s a kilobyte? A megabyte?

Let’s start with the basics. A byte is the smallest unit of information a computer uses: a set of (usually) eight numbers that define a single character such as a letter, a comma, or a number. So the letter B is one byte of information while antidisestablishmentarianism is 28 bytes.

Multiple bytes are distinguished by prefixes to show size, so rather than saying a computer has four billion (4,000,000,000) bytes of memory, we refer to it as having four Gigabytes. The prefixes currently used to refer to the number of bytes are Kilo- (one thousand or 1,000), Mega- (one million or 1,000,000), Giga- (one billion or 1,000,000,000) and Tera- (One trillion or 1,000,000,000,000). Let’s see this in practice.

One of the first personal computers offered was the IBM Personal Computer XT model 5160 in 1983. At the time, it was an unbelievable machine with a base of 128 Kilobytes of memory (128KB) and 10 Megabytes (10 MB) of storage. It cost nearly $2,000, close to $5,500 in today’s economy.

When Apollo 11 took a man to the moon, the onboard computer (the Apollo Guidance Computer) was amazingly compact for its time, measuring just under two feet in length, a foot wide and five inches thick. Memory was four Kilobytes while the total storage of the system was 72 Kilobytes. As a comparison, this article would take up about 20% of the Apollo computer’s memory at 16 Kilobytes. Solitaire? Forget it; the file for that program is around 180 Megabytes.

A typical personal computer today has eight Gigabytes of memory and 500 Gigabytes of storage and costs around $800 for a good quality system. Technology has made systems smaller, less expensive, and capable of carrying more data. Is there an upper limit to how much data a computer system can have? Yes, but that figure is growing by leaps and bounds. The highest official measurement used for data today is a yottabyte: one septillion (1024) bytes, roughly equivalent to all of the Internet traffic for the entire year of 2016, times 950.

Don’t look for that on the shelves anytime soon.

Some of you are also wondering what the word “antidisestablishmentarianism” means and if it’s real. It’s the belief a state Church should continue to receive government patronage rather that be removed as the government’s official religion, which dates back to 19th-century Britain when there was a movement to “disestablish” the Anglican Church as being the official state church of Britain. It’s considered one of the longest words in the English language that’s not related to science. Thank you for attending History 101 today.

Remember, if you’ve got a question you’d like answered, send me an e-mail at .