(1) A location of data, usually in main memory or on a disk. You can think of computer memory as an array of storage boxes, each of which is one byte in length. Each box has an address (a unique number) assigned to it. By specifying a memory address, programmers can access a particular byte of data. Disks are divided into tracks and sectors, each of which has a unique address. Usually, you do not need to worry about addresses unless you are a programmer.
(2) A name or token that identifies a network component. In local area networks (LANs), for example, every node has a unique address. On the Internet, every file has a unique address called a URL.