Do you remember the first Personal Computer (PC)? This is a nostalgic quiz which takes you back to the days of the IBM PC by using numbers that were significant in those early days of personal computing. See how many of these numbers you can remember. When you’re done with these numbers try the two quizzes below.

**Number number one: 8088**

The first number we look at is 8088. Do you remember it? Click on the first (left-most) list item for the answer to this number.

Do you remember DOS? Take the DOS trivia quiz. Are you internet savvy? Take the internet trivia quiz.

## 8088?

The first number is 8088, which is the number for the Intel 8088 CPU, the microprocessor used in the original IBM PC. It had a sibling, the 8086 CPU which was a 16-bit version and the 8088 was an 8-bit version. The designers of the IBM PC chose the 8088 because it was cheaper.

**Number number two: 640K**

See if you can guess the relevance of this number and then click the next list item to find out if you are right.

## 640K?

The first PCs had a maximum of 640 kbytes of memory. That is 655,360 bytes. One byte can hold roughly one character (letter or number) or one program instruction (although some instructions require more than one byte). Bill Gates once said “640 kbytes of memory ought to be enough for anyone.” Today’s computers use multiples of gigabytes of memory – four gigabytes is 6,250 times the memory of those early computers. Bill, I think you were wrong.

**Number number three: 4.77**

How does this number relate to early PCs? Click on the next list item to read about this number.

## 4.77?

4.77 megahertz was the clock speed of the first IBM PC. Today’s computers run at about 2 to 3 gigahertz or faster with 3.2 gigahertz being among the fastest of the Intel processors. The faster the clock speed, the faster the computer can process information and get things done. Today’s computers are much faster, in fact a 3.2 gigahertz processor is a whopping 671 times faster than the original IBM PC clock rate!

**Number number four: 5150**

Go to the next list item for the answer to this number.

## 5150?

The very first IBM PC model number was 5150. The IBM XT, an “enhanced” version of the original PC, had both diskettes and hard drive storage. The first hard drive was a ‘full-height’ drive which was about four inches high. You had to ‘park’ the heads before turning off the computer. This hard drive was a whopping 10 megabytes in size. We’ve come a long way.

**Number number five: 5.25**

Click on the next list item for the answer to this number.

## 5.25?

The original IBM PC had 5.25-inch diameter floppy drives. The IBM XT had the first hard drive which was also a 5.25-inch form factor drive. Later models had 3.5-inch floppies and hard drives and eventually floppies were completely removed as storage devices. A 3.5-inch has one-half of the surface area of a 5.25-inch drive and a 2.5-inch drive (the size of hard drives used in laptops and many computers today) is half of the surface area of 3.5-inch drives. Today’s hard drives are around one or two terabytes, and a two terabyte drive is 200,000 times more capacity than the original 10 megabyte drive in the XT!

That’s all of the numbers for now, I hope you enjoyed reminiscing about the “good old days” of personal computers. Be sure to take the other two quizzes listed in the main article. See how much you remember about DOS and how much you really know about the internet.