Sessions & Tracks : Sessions : Bit Depths and Sample Rates : Sample Rates

Sample Rates
44.1 kHz
Is the sample rate used for CDs and is used in most common music production environments.
48 kHz
Is the standard sample rate for film and video projects, and is commonly used in post-production environments. It is the sample rate used for DVDs.
88.2 kHz and 96 kHz
Each of these sample rates are twice the standard sample rates for CD audio and DVD audio respectively. Audio files recorded at higher sample rates take up more drive space, but provide higher resolution for time-based plug-in processing (which can help avoid aliasing). The 88.2 kHz and 96 kHz sample rate options are only available if you are running Pro Tools with audio hardware that supports these sample rates.
172.4 kHz and 192 kHz
Each of these sample rates are four times the standard sample rates for CD audio and DVD audio respectively. Audio files recorded at higher sample rates take up more drive space, but provide higher resolution for time-based plug-in processing (which can help avoid aliasing). The 176.4 kHz and 192 kHz sample rate options are only available if you are running Pro Tools with audio hardware that supports these sample rates.