Final answer:
A sound card is a circuit board that converts sound from analog to digital form, and vice versa, for recording or playback.
Step-by-step explanation:
A computer's sound card is a circuit board that converts sound from analog to digital form, and vice versa, for recording or playback. The sound card contains components such as an Analog-to-Digital Converter (ADC) and a Digital-to-Analog Converter (DAC).
For example, when you speak into a microphone connected to your computer, the sound waves are converted into electrical signals in analog form. The sound card then converts these analog signals into digital data that can be processed and stored by the computer.
Similarly, when you play a digital audio file, the sound card converts the digital data back into analog signals that can be amplified and sent to the speakers.
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