"In this lesson, we discuss more about stability issues. A popular buzzword these days is 'interface.' That's just a fancy word implying that two or more people are face to face. In actual practice, it usually means anything but face to face. It's a means of interacting with another. You are said to 'interface' by some means. So it is with computers.
"Way back when the personal computer was first introduced, there was a machine called the 'Altair.' It was a big box with some switches and lights. You were supposed to know what the switches did, and what the lights told you. It was basically a fancy number cruncher. Except, the numbers were in binary, and up to 8 places. Eight switches could be up or down, representing the eight digits allowed in a binary number. Think back to your school math days, and you may recall that binary means 1s and 0s only. That's because the electronic computer was based on--surprise!--electricity. With electricity, it's a simple matter of on or off. If you couldn't think in binary numbers, the Altair was pretty hard to use..."
