|A Modem and a Router are two completely different devices doing completely difference jobs but often come combined in a single box. The ability to connect more than one computer is the function of a switch, something that also comes combined with a a Modem/Router.|
A Modem takes the DSL signal and DEModulates it and send the data out as Ethernet. It also take an outgoing Ethernet signal and MODulates it into a DSL signal for transmission over the telephone line.
A routers function is to connect two networks together. In this case the Internet and your Local network.
A switch is for extending a local network so that one connection can serve to or more computers.
A wireless router is simply a wired router with a built in Wireless Access Point.
So you need a Modem at the very least. If you only have one computer a Modem will suffice but it is advisable to install a Router as well even though you only have one computer as the Router will give you some protection from unauthorised access.
You need to decide whether to use a separate Modem and Router or buy a box with a combined Modem and router. The latter is preferable as it means less wires trailing all over the place. As most routers also come with a built in four port switch you have no need to buy another one unless your network expands to more than four computer.
With that in mind all you have to decide it how much you are prepared to pay. As to which is the best, they are all pretty much the same. You pays your money and takes your choice.
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