PST may refer to any of the following:
1. Short for Pacific Standard Time, PST is a world time zone. See the time definition for further information about time and time zones.
2. Short for Please Send Tell, PST is commonly used in computer gaming for when users want other users to send them a message if they are interested in something. For example, a user could say "WTB sword for 1g, PST", which means they are interested in buying a sword for one gold piece.
3.Short for Personal STore, .PST is a post office box file used with Microsoft Outlook that stores the e-mail, calendar, contacts, notes, journal, and other data used with Outlook.