A product key, also known as a software key, is a specific software-based key for a computer program.

It certifies that the copy of the program is original.

Activation is sometimes done offline by entering the key, or with software like Windows 8.1, online activation is required to prevent multiple people using the same key.

Not all software has a product key, as some publishers may choose to use a different method to protect their copyright, or in some cases, such as free or open source software, copyright protection is not used.

Microsoft Office is an office suite of applications, servers, and services developed by Microsoft.

It was first announced by Bill Gates on 1 August 1988, at COMDEX in Las Vegas.

Initially a marketing term for a bundled set of applications, the first version of Office contained Microsoft Word, Microsoft Excel, and Microsoft PowerPoint.

Over the years, Office applications have grown substantially closer with shared features such as a common spell checker, OLE data integration and Visual Basic for Applications scripting language.

Microsoft also positions Office as a development platform for line-of-business software under the Office Business Applications brand.

On 10 July 2012, Softpedia reported that Office is used by over a billion people worldwide.

Microsoft Windows (or simply Windows) is a metafamily of graphical operating systems developed, marketed, and sold by Microsoft.

It consists of several families of operating systems, each of which cater to a certain sector of the computing industry with the OS typically associated with IBM PC compatible architecture.

Active Windows families include Windows NT, Windows Embedded and Windows Phone; these may encompass subfamilies, e.g. Windows Embedded Compact (Windows CE) or Windows Server.

Defunct Windows families include Windows 9x; Windows 10 Mobile is an active product, unrelated to the defunct family Windows Mobile.

NET Framework (pronounced dot net) is a software framework developed by Microsoft that runs primarily on Microsoft Windows It includes a large class library named Framework Class Library (FCL) and provides language interoperability (each language can use code written in other languages) across several programming languages Programs written forNET Framework execute in a software environment (in contrast to a hardware environment) named Common Language Runtime (CLR), an application virtual machine that provides services such as security, memory management, and exception handling (As such, computer code written usingNET Framework is called "managed code") FCL and CLR together constituteNET Framework.