The sample rate refers to the number of samples of audio recorded per second, measured in Hertz (Hz). For example, a sample rate of 44.1 kHz means that 44,100 samples are taken every second. This rate is crucial in digital audio because it determines the quality and fidelity of the sound being captured or played back. Higher sample rates can capture more detail in the audio, making it sound clearer and more accurate. Common sample rates include 44.1 kHz for CDs and 48 kHz for video production. However, higher sample rates also require more storage space and processing power.