Sample rate measures how many times per second an audio interface measures (samples) the analog audio signal and converts it to a digital number. The Nyquist theorem states that the maximum frequency that can be accurately captured is half the sample rate. At 44,100 Hz (44.1 kHz), the maximum captured frequency is 22,050 Hz — well above the 20 kHz limit of human hearing.
44.1 kHz is the CD audio standard and remains the most common format for music. 48 kHz is the standard for video production, broadcast, and podcasting. All modern audio interfaces support both rates and can switch between them in software.
96 kHz and 192 kHz are marketed as 'high resolution' and provide some benefits for recording: more headroom when pitch-shifting, a steeper filter slope in the analog chain, and a safety margin when the final output will be 48 kHz. However, for most home recording applications, 48 kHz is entirely sufficient.
Recording at higher sample rates creates larger files. At 96 kHz, a stereo recording uses about twice the storage of a 48 kHz recording. For a podcast or stream, this additional storage and processing overhead provides no audible benefit.