The editions of SQL Server 2008 are as follows:
- Enterprise: this is the high-end edition with the full feature set. It supports systems up to 8 CPU and 2 TB RAM. The maximum size of the database is 524 PB.
- Standard it has a bit less features than Enterprise, but it is a good choice when advanced functions (such as data compression, compressed backups, indexed views, etc.) are not required for the business. It supports systems up to 4 CPU and 64 GB RAM.
- Workgroup: it is suitable for remote offices of a larger company. It supports systems up to 2 CPU and 4 GB RAM.
- Web: it is designed for web applications. It supports 4 CPU without memory limitations.
- Developer: similar to Enterprise, but licensed to only one user for development, testing and demo. It can be easily upgraded to Enterprise without reinstallation.
- Express: free entry level database. It can utilize only 1 CPU and 1 GB memory, the maximum size of the database is 10 GB.
- Compact: free embedded database for mobile application development. The maximum size of the database is 4 GB.
Another point of interest is that SQL Server Analysis Services and SQL Server Integration Services are included only in Enterprise and Standard Edition. SQL Server Reporting Services is also very limited in the free editions.