Some major differences:
1-XP Pro systems can join a domain; XP Home systems can't, which limits its use to home and SOHO environments because it can't use any corporate-specific features such as IntelliMirror.
2-Microsoft Internet Information Services (IIS) 5.1 and Personal Web Server (PWS) are found only in XP Pro.
3-Direct access to the Administrator account is available only in XP Pro. XP Home users must log on using Safe mode to access the Administrator account.
4-XP Pro supports Remote Desktop, which is basically a single-user version of Windows 2000 Server Terminal Services. XP Home supports only Remote Assistance.
5-Networking-related Group Policy Objects (GPO) are available only in XP Pro. XP Home supports no group policies.
6-Microsoft Remote Installation Services (RIS) and Sysprep are supported only in XP Pro.
7-The Network Monitor application is available only in XP Pro.
8-The UI for IP Security (IPSec) is available only in XP Pro.
9-SNMP support, Simple TCP/IP Services, the service access point (SAP) and Client Services for NetWare (CSNW) are available only in XP Pro.
10-XP Home supports only simple file sharing. Detailed file-level security permissions such as those found in Win2K are available only in XP Pro, which also supports the simple file-sharing model that XP Home uses.
11-XP Pro lets users limit the number of connections to shared folders and control user access by account. XP Home users access shared folders through the Guest account, which is disabled by default in XP Pro.
12- You can upgrade Windows NT 4.0 Workstation and Win2K Professional only to XP Pro. You can upgrade Windows 9x versions since Windows 98 only to XP Home. Neither version supports upgrades from Windows 95.