-- this uses the system metadata tables
SELECT * FROM sysobjects
WHERE type = 'U'
GO

-- this uses the INFORMATION_SCHEMA
SELECT * FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
GO

-- underlying system views
SELECT * FROM sys.tables
GO

SELECT * FROM sys.assemblies
GO

SELECT * FROM sys.assembly_files
GO

SELECT * FROM sys.assembly_references
GO