Definition

COM is not an acronym unlike many of the other ports; it simply stands for the "com" in communications. It is commonly known as the serial port because it was the first port to use that type of communication. Widely use since personal PCs became a common tool. Are cheap and can be used with longer cables than parallel ports. Like the LPT port it is shaped like a trapezoid, but smaller, with the short end in the bottom and has 9 pins divided in 2 rows, one with 5 and other with 4 (be careful not to confuse it with the monitor port which is similar in size and shape but it has more pins and it is use only for monitors.) Commonly used to connect the mouse, keyboard, modems, cameras, and PDAs, especially before USB ports appeared. There are usually more than one COM port in a computer and to differentiate them they are labeled with a number after COM. Commonly there are COM 1 and COM2 available. A typical COM port reaches speeds of 115Kb/sec.

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Pictures

COM Port - Socket	COM Port - Plug

Symbol

COM Port Symbol (Newer Models)	COM Port Symbol (Older Models)

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Advantages

COM ports are very versatile. Many types of peripherals have used the COM port traditionally. Though, with the advent of USB, the use of COM ports is dwindling.

Common Peripherals

As mentioned above, COM ports are extremely versatile. They have be used to connect mouses, keyboards, modems, cameras, and PDAs, to name a few.

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Practice

Answer the following questions. Try not to look at the information above.

1.	Your spouse gave you a digital camera for Christmas. The camera requires a COM port. Which of these ports would you plug it into?
2.	You just bought a new mouse that comes with both USB and COM port connections. You are not sure which cord to use, but you notice a symbol on the package that represents the COM port. What does that symbol look like?

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