A sound card (also known as an audio card) is a computer expansion card that facilitates the input and output of audio signals to and from a computer under control of computer programs. Typical uses of sound cards include providing the audio component for multimedia applications such as music composition, editing video or audio, presentation, education, and entertainment (games). Many computers have sound capabilities built in, while others require additional expansion cards to provide for audio capability. Sound cards come in many forms, for the most part, the lower end sound cards come built onto the motherboard. But the motherboard contains PCI slots which allow further expansion if needed. Sound cards also now come in USB form for laptops and net books, for which it is harder to take apart and fit a new expansion cards. Therefore am external USB sound card can be inserted. Although these are more commonly thought of as Audio interfaces rather than sound cards as the sound comes from software within the PC/Laptop, the USB card provides an interface with Headphone and Mic jacks.
The interface type is the type of Computer BUS that sound card is compatible with. For sound cards this is commonly PCI (Peripheral Component Interconnect)
Any device which allows the user modification of the program signal.
Sound Output Mode
This is the output capability the sound card has, such as Dolby Digital Surround Sound 5.1 or 7.1.
DAC Data Width
Digital to Analog Converter, is the rate at which it can convert digital data to Analog. Computer input is in Binary, digital input, Sound is output as Analog, therefore needs to be converted.
Sample rate describes how frequently an analog audio signal is sampled as it is converted into a series of numbers.
Signal to Noise Ratio
A comparison of the signal level relative to the noise level. Larger numbers are better.