In physical and chemical terms, an interface is the line or point of contact between two separate media, such as between water and air. In computing, the term interface has several meanings.
The most common definition of interface refers to the way a computer interacts with the user (and vice versa), usually used to describe either a command-line interface, in which text-based and somewhat cryptic commands are entered via a keyboard, or a graphical user interface, in which icons, windows, and dialog boxes are clicked on using a mouse or other similar device. The latter is often described as more user-friendly. See Command-Line Interface and Graphical User Interface. This type of interface is commonly known as a user interface or software interface.
The term interface also refers to the means by which two hardware components of a computer system interact with each other, usually involving some means of software control. For example, different computer systems have different interfaces between the CPU and peripheral devices connected tyo it. On the Apple Macintosh and increasingly Windows-based PCs, the Small Computer System Interface is the means by which attached disk drives, CD-ROM drives, scanners, etc., communicate with the CPU. Peripheral devices—including printers and modems—also need device drivers, which are the primary software component of the interface. This type of interface is commonly known as a hardware interface.
The term interface also refers to the means by which a computer is connected to a network, faciliating the transfer of data from node to node.