Question: Why is memory measured in bytes and communications in bits?

Answer: First, let’s define bits and bytes. A bit is a single binary digit and can be a zero or a one. It is the most basic storage unit on the com-puter. A byte is eight bits and is the basic way of managing bits. Tradi-tionally, it took one byte to store a single character we use. However, as computers became international, we could not store all characters of human languages in one byte. So normally today it takes two or 4 bytes to store a single human character.

Memory and disk storage capacity is normally stated in bytes as they correlate closely to human characters. So traditionally, if it was said you have 100 million (100 mega) bytes of storage, you could store about 100 million human characters. Of course, space for pictures are in terms of millions of bytes per picture, so it really is not that simple anymore.

When information is sent across the Internet or thru our network, it is put on a communications channel. These channels, whether telephone line, Ethernet cable, wireless, fiber or whatever, work on one bit at a time being sent (although our bytes have been put in groups called packets or frames that have addresses on where to and from and more information). Then they are received by the receiving device one bit at a time Since it is only being sent a bit at a time, speeds of communications are expressed as some number of bits per second (bps), today normally in megabits per second or gigabits per second. There used to be one exception to this rule, and that was earlier printers often used a parallel port which meant there were 8 wires in the cable and they transmitted eight bits (or a byte) at a time. However, today printers use USB (a serial communications line) or serial cabling, so they work one bit at a time.

Send your questions about computers to me at the paper or to my e-mail (dwight@dwightwatt.com) and tell me you read this in this paper. I will pick a question to answer each week.

Dwight Watt does computer work for businesses, individuals and organizations and teaches about computers at a college in Northwest Georgia. His webpage is www.dwightwatt.com, and his e-mail address is dwight@dwightwatt.com.