The term "44.1 kHz" refers to the standard sampling rate used in digital audio, particularly for CDs. It indicates that audio is sampled 44,100 times per second. This rate was chosen because it can accurately capture the full range of human hearing, which typically extends up to 20 kHz, while also allowing for some headroom to avoid distortion. In digital audio, sampling is crucial for converting sound waves into a format that computers can process. The higher the sampling rate, the more detailed the audio representation. However, 44.1 kHz strikes a balance between sound quality and file size, making it a popular choice in the music industry and for digital audio formats.