How do I know if I need to install a router for my computer?

My sister and I both had our own computers and were using the internet. We both had our own modems without having a router. Now Com-cast says we need to have a router, is this true? Also how do install a router?How do I know if I need to install a router for my computer?
Were you using dialup before and now getting broad band?



A dialup modem is nothing like a Cable Modem.



If you are switching to broadband a router is the easiest set up for connecting pc's/laptops to broad band.



They may mean that you can not have multiple computers without a router.



Actually, if the Cable Modem can interface to one computer and the other is near by, you could use a cross over cable and to connect the 2nd computer and share the internet that way. You would just bridge the connections in your network setup on the 1st computer. Both computers would have to have ethernet connectors for this to work. Most modern computers come with ethernet connections, but not all.



However a router would make things easier.



There are two types of routers, wired and wireless.



A wired router would connect to Comcast's Cable Modem, giving the router Internet acces,(WAN-Wide Area Network). Then cables would run from the router to each computer, creating your LAN-Local Area Network. The router allows the computers to share the WAN and communicate with each other, (share files). Most routers come with four ports, four places to connect computers.



A wireless router would connect to Comcast's Cable Modem the same way. But the connection to the computers would be with no cables. Each computer would need a wireless network adaptor. Most laptops have a wireless network adaptor build in. If you need to buy some, you can buy cards that go into a tower, usb adapters that plug into a usb port, and adapters for laptops. A wireless router can share the internet, (wan), with up to 128 or so computers. Some wireless routers also have wired ports for connecting cables directly, essentially being a wired/wireless cross.



Routers also have built in firewalls, that make the whole network more secure.How do I know if I need to install a router for my computer?
Two modems on DSLCable?

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A router connects two or more computers to one modem,

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The router can be wired or wireless.

- Wireless prevents a tangle of wires connecting computer.

- Wireless may mean purchasing and installing wireless adapters in the PCs.