What Is an Interface in Computing?
An Interface is a shared boundary across which two or more separate components of a computer system exchange information, such as USB or HDMI. The exchange can be between software, computer hardware, peripheral devices, humans, and combinations of these. Some computer hardware devices, such as a touchscreen, can both send and receive data through the interface, which other such as a mouser or microphone may only provide an interface to send data to a given system.
The use of interfaces allows for a programming style called programming to the interface. The idea behind this approach is to base programming logic on the interfaces of the objects used, rather than on internal implementation details. Programming to the interface reduces dependency on implementation specifics and makes code more reusable.
Two Types of Interfaces
- Hardware interfaces: they exist in many components, such as the various buses, storage devices, other I/O devices. A hardware interface is described by the mechanical, electrical, and logical at the interface and the protocol for sequencing them (sometimes called signaling). A standard interface, such as SCSI, decouples the design and introduction of computing hardware, such as I/O devices, from the design and introduction of other components of a computing system, thereby allowing users and manufacturers great flexibility in the implementation of computing systems. Hardware interfaces can be parallel with several electrical connections carrying parts of the data simultaneously or serial where data are sent one bit at a time.
- Software interfaces: Here we only talk about in Practice. A key principle of design is to prohibit access to all resources by default, allowing access only through well-defined entry points, i.e., interfaces. Software interfaces provide access to computer resources (such as memory, CPU, storage, etc.) of the underlying computer system; direct access (i.e., not through well-designed interface) to such resources by software can have major ramifications -sometimes disastrous ones – for functionality and stability. Interfaces between software components can provide constants, data types, types of procedures, exception specifications, and method signatures. Sometimes, public variables are also defined as part of an interface.
In PCB design, manufacturing and assembly, we always meet various types of interfaces for programming, connection, data transfer. Some have computer configuration requirements, some have power supply requirements, some have PCB thickness and impedance control requirements (especially for high speed designed boards).