Pocket PC 2000 (marketed as Pocket PC) was the first member of the Windows Mobile family of mobile operating systems that was released on April 19, 2000, and was based on Windows CE 3.0. It is the successor to the operating system aboard Palm-size PCs; backwards compatibility was retained with such Palm-size PC applications. It was mainly intended for Pocket PC devices, however several Palm-size PC devices had the ability to be updated also. Furthermore, several Pocket PC 2000 phones were released (under the name Handheld PC 2000), although Microsoft's "Smartphone" hardware platform had not yet been established at that time.
Aesthetically, Pocket PC 2000 was meant to be similar in design to the then-current Windows 98 and Windows 2000 desktop operating systems, as well as the yet-to-be-released Windows Me (which was still in development at the time of Pocket PC 2000's release). It had multiple built-in applications, many of them similarly branded to match their desktop counterparts, such as Microsoft Reader, Microsoft Money, Pocket Internet Explorer, and Windows Media Player. A version of Microsoft Office called Pocket Office was also bundled and included Pocket Word, Pocket Excel and Pocket Outlook. Notes, a note-taking app saw its first release and would be supported by most later versions of Windows Mobile.