To connect two computers you need each computer have a functioning network interface with an external jack for the cable, and the network settings on each computer appropriately configured. This is minimum requirement.
Some Basic network devices & Components
Hubs, switches, and routers are three examples of network devices. Generally, a network device is anything that functions as a building block or connector for a network. The type of device required depends on the function of a particular segment of the network.
Hubs
The hub is the simplest device. It's a simple piece of hardware that generally contains four to 32 network ports and is used to inexpensively connect multiple computers or other devices together. A hub receives transmissions on one of its ports and automatically echoes the data to every other port. A hub doesn't filter or process network traffic in any way -- it's an inexpensive, simple way to connect nodes to a network.
Switches
The next type of network device is the switch (also called switching hub or intelligent hub). A switch is similar to a hub, but instead of blindly echoing a transmission to all nodes, the switch reads the destination machine's address -- its MAC address (media access control) -- and creates a direct connection between the sending and receiving nodes. All further communication between the nodes is handled directly and is not visible to other nodes. This capability requires more expensive hardware than a hub, but provides security and enhanced performance. Also, a switch can maintain several direct connections simultaneously, reducing network collisions and increasing overall network speed.
Wireless access points (AP)
If you decide to build part or your entire network to support wireless connections, you'll need a device that allows computers with wireless adapters to connect to the network. This device is called a wireless AP (access point). APs have become very popular and are available in nearly all price ranges with a wide variety of features. Some APs are integrated with switches or other high-level network devices.
Routers
One of the most sophisticated network devices is the router. A router is similar to a switch, except that it looks inside the message to find the destination IP address. This is different from a switch; a router must do more work to read the contents of the message header to find the IP address. Based on that information, the router then determines where to send the message. Routers are generally connected to more than one network and their main function is to route messages from their source to their destination networks and nodes. APs are commonly bundled with routers to create wireless router devices.
Print servers
A print server connects a printer to a network. This is one of two common methods of connecting a printer to a network. A print server contains the functionality to receive print jobs, store them in memory, and send them to a connected printer. You can easily find both wired and wireless printer servers.
Consider a print server if multiple people routinely share a printer. In many offices, sharing a printer involves attaching it to a computer on the network, then sharing it through that computer. That works well as long as the computer is on. A print server allows anyone to use a printer without requiring that an attached computer be up and running.
Internet access devices
The last component you need on your network is an internet access device that connects you to the internet. The type of device you need depends on the type of internet connection and service you purchased. Most small businesses connect to the internet either by dial-up, cable modem, or DSL (Digital Subscriber Line).
The slowest method of connecting to the internet, or any other network, is using a dial-up modem. Most dial-up modems operate at a maximum speed of 56 Kbps (kilobits per second). Dial-up modems used to be the primary method for connecting to other networks; however, that option is fast becoming obsolete. Although many ISPs (internet service providers) still support dial-up service, the slow data access rate makes it frustrating to use in a business environment. If cable or DSL access is available, use one of them instead of dial-up to access the internet.
The next two types of internet access are referred to as high-speed access methods because their data transfer rates are many times faster than dial-up. Both cable and DSL internet service use special modems to connect the network to the internet. You can purchase the special modems from computer retailers or directly from your ISP. Although different in their internal organization, all three modems (dial-up, cable, and DSL) serve to connect a computer or device to the internet.