Knowledge Hub

License Glossary

What separates Retail from OEM? What is a MAK key? Why is KMS risky? We explain the licensing world's confusing terms with short, clear, honest definitions — so you choose the right license knowingly.

• Retail LicenseA Retail license is the standard license type Microsoft sells to individual users through retail channels. Sold boxed or digitally, it is activated for use on a single computer.Read the definition
• OEM LicenseAn OEM license is a license type designed for computer manufacturers that binds to the hardware (motherboard) it is installed on. It is usually the most economical permanent option.Read the definition
• MAK (Multiple Activation Key)A MAK is a key type Microsoft produces for organisations in its volume licensing program, carrying a set number of activation rights. Each activation draws down the key's total allowance.Read the definition
• KMS (Key Management Service)KMS is a legitimate enterprise infrastructure Microsoft provides so large organisations can activate Windows and Office in bulk on their own networks. Pirated 'KMS activators' are fake imitations of it.Read the definition
• BIND License (Account-Bound)A BIND license is a licensing model where the product is registered to your Microsoft account. The license lives in your account rather than in a key; as long as you sign in with the same account, you can re-download and reinstall the software.Read the definition
• Volume LicensingVolume licensing is Microsoft's program for selling organisations hundreds or thousands of licenses under a single agreement, at unit prices far below individual retail. It is the main source of affordable genuine keys.Read the definition
• Digital LicenseA digital license is the modern activation method where Windows stores its activation state by pairing a hardware ID and/or Microsoft account instead of a product key.Read the definition
• Product KeyA product key is the 25-character (5x5) code that verifies a software's authenticity. It is validated on Microsoft's server during activation and registers the license to the installation.Read the definition
• ActivationActivation is the process of verifying on Microsoft's server that your copy of Windows or Office is genuine. After successful activation the software runs fully featured, without restrictions.Read the definition
• ESU (Extended Security Updates)ESU (Extended Security Updates) is Microsoft's paid program of additional security updates for Windows versions past end of support. It brings no new features; it provides critical security patches only.Read the definition
• TPM 2.0TPM 2.0 (Trusted Platform Module) is a security chip that stores encryption keys at the hardware level and is one of Windows 11's official installation requirements.Read the definition