Microsoft® Manual of Style, Fourth Edition

General guidelines

Do not specify a particular version unless it is necessary for the context. For example, you may need to specify the version number when comparing current and previous versions of the same product or for reasons of clarity and technical accuracy. Do not include the update identifier of a product unless it is technically relevant.

If you must mention a version number, specify it on first mention in a topic or section. Thereafter, refer only to the product name without the version identifier. For products whose original release identifier includes .0, use .x (in italic type) to indicate all release numbers of a product.

Microsoft style

This topic applies to .NET Framework 3.x. (Indicates all releases of .NET Framework.)

You may use ...