what exactly does a modem do? and does it have memory?

Question

i rent one from a cable company and im just curious as to what these machines do.

Answer 1

Modems translate the signal coming on on the cable line into a format that your computer can use. They have enough memory to remember some basic settings.

Answer 2

A cable modem is a device that connects a computer system to the Internet via the cable television network. Cable Internet technology allows for transfer rates as high as 30Mbps (megabits per second, or 30 million bits per second; contrast that to phone modems at 56 thousand bits per second). However, that bandwidth is commonly divided up among all subscribers in a defined area, such as a neighborhood or a subdivision. Because of this, real world transfer rates are anywhere from 256Kbps to 4Mbps. The most common way to link to the cable modem is through an Ethernet 10BASE-T connection.

The term "cable modem" implies that it functions like a plain old telephone modem. This is not the case. A cable modem Internet connection is always on. You don't dial up anymore; just having the computer turned on is enough to be connected. Most users familiar with Ethernet should treat a computer connected through a cable modem exactly as they do one connected to an Ethernet network.

Increasingly, things are changing so that a cable modem isn't really a modem any longer; that is, it's not a device that modulates and demodulates a signal between an analog network and a digital end device. For example, a phone modem modulates a digital signal from the computer into an analog signal for the phone lines, and demodulates the analog phone signal into a digital one. The first cable modems did the same thing, except with a cable TV signal. But now, things are changing. Many cable Internet service providers (ISPs) are migrating towards a fully digital network for everything, including their television signals. This means that cable modems on those systems will no longer be modems; they will more properly be called media converters or cable terminal devices (this is the term the cable TV industry says is the proper one).

Answer 3

a modem basically hooks more than 1 computer up to an internet line

that's a dumbed down version since i presume you don't know too much about computers and stuff related to it.
just plug it into a cable line
plug the other computers in (unless u have wireless)
plug a main computer in to download software
and ur Good to GO

Answer 4

http://computer.howstuffworks.com/modem.htm