A personal information manager is a type of software program that aids in managing all kinds of personal information, including contacts, pictures, and personal journals as well as notes and workplace papers. A PIM app can be a complete set of tools that handles various kinds of information, or it can concentrate on one specific category of information, such as a planner or note-taking app. Since most operating systems now come with a few basic built-in PIM tools, such as email applications and diaries, many third-party PIM apps concentrate on refining those features and enhancing their functionality.

The data put into PIM software is kept in a directory. The database's notes, stored papers, meetings, and other data are all readily accessible. Some PIM software keeps that information in the cloud and makes it available through a web browser or multiple devices. Some PIM files can be protected to keep the data safe because this confidential information may be present.

Portable digital assistants like the Palm Pilot and the Mac Newton had PIM software as a key component. Mobile operating systems now have a large PIM feature set as cellphones have largely supplanted PDAs. In addition to the calendar, contacts, and note-taking applications that come pre-installed on smartphones, some well-liked PIM software programs are Evernote, Microsoft OneNote, and DEVONthink.