|  | 3.1 | Basic LAN Devices
| 3.1.11 | Network segments
The term segment identifies the layer 1 media that is the common path for data transmission in a LAN. On the media page, one thing that was mentioned is that there is a maximum length for data transmission for each type of media. Each time an electronic device is used to extend the length or manage data on the media a new segment is created. The devices that are used to create new segments are covered in the rest of the pages of this chapter. Some people refer to segments by the term, wires, though the "wire" might be optical fiber, wireless medium, or copper wire. The function of the different segments of a network are to act as efficient local LANs that are part of a larger network. Segment is an important word that you will hear often. The word segment, as it applies to LANs, is completely different from the word that describes a Layer 4 PDU. Here, it means segments of the network.