limitations of express edition

What are the limitations of sql server express edition? For example oracle released Oracle express and its limitation is of maximum user data size of 4 gb.

Have a look at the following document, which compares the SQL Server editions:

SQL Server 2005 Features Comparison|||Thanks a lot. This is exactly what I was looking for.|||SQL Server 2005 Features Comparison - this chart is not so detailed as I need. In comparison table for SQL 2000 was item about http/https connectivity (supported only by SQL 2000 Enterprise Edition) but in the comparison table for SQL 2005 is missing. Could you help me - I'd like to now if I need SQL 2005 Enterprise Edition for http/https connection to Analysis Services or it is already possible with Standard Edition.
Thanks