Two concepts for SQL Server

server| concept
The page is the most basic data storage unit of SQL Server, with 8KB per page in SQL Server, which means that the SQL Server database has a total capacity of 128 pages per trillion data files.

Type of page: Data, index, text/image, global data distribution, page free space, index distribution image.

A scope (extent) is the most basic unit of storage space allocated to a table or index by a SQL SERVER database. Each range consists of 8 consecutive pages. That is, the SQL SERVER data file can hold up to 16 ranges per megabyte. However, to improve the efficiency of using space, SQL Server does not allocate a single range of space for a small data table with only 200 bytes. SQL Server therefore provides two types of scope:

Uniform scope: The scope of a unified type assigns all 8 data pages to the same table or index, which can only be used by this table or index.

Blending range: A range of mixed types can be shared by 8 of database objects.