# Fundamental Concepts

- [License Key Fields Definitions](/docs/fundamental-concepts/license-key-fields-definitions.md)
- [License Key Types](/docs/fundamental-concepts/license-key-types.md)
- [Length of QLM license keys](/docs/fundamental-concepts/length-of-qlm-license-keys.md)
- [OrderStatus field](/docs/fundamental-concepts/orderstatus-field.md)
- [License Model](/docs/fundamental-concepts/license-model-1.md)
- [License Model v17+](/docs/fundamental-concepts/qlm-license-models.md)
- [Computer Identifier (ComputerID) requirements](/docs/fundamental-concepts/computer-identifier-computerid-requirements.md)
- [License Binding](/docs/fundamental-concepts/licensebinding.md)
- [Variable License Binding](/docs/fundamental-concepts/variablelicensebinding.md)
- [Product Features](/docs/fundamental-concepts/qlm-features.md)
- [Product Properties](/docs/fundamental-concepts/product-properties.md)
- [Data Types](/docs/fundamental-concepts/product-properties/data-types.md)
- [Enforce Product Properties](/docs/fundamental-concepts/product-properties/enforce-product-properties.md)
- [CommunicationEncryptionKey and AdminEncryptionKey](/docs/fundamental-concepts/communicationencryptionkey-and-adminencryptionkey.md)
- [Search macros](/docs/fundamental-concepts/definition-of-the-macros-that-can-be-used-in-searches.md)
- [Differences between QLM Express and QLM Pro](/docs/fundamental-concepts/whats-the-difference-between-qlm-express-and-qlm-pro.md)
- [Differences between QLM Pro and Enterprise](/docs/fundamental-concepts/what-is-the-difference-between-qlm-pro-and-enterprise.md)
- [Server-side license validation](/docs/fundamental-concepts/server-side-license-validation.md)
- [Online activation](/docs/fundamental-concepts/how-does-online-activation-work.md)
- [Online Activation with basic authentication (user/password)](/docs/fundamental-concepts/how-does-online-activation-work/online-activation-with-basic-authentication-user-password.md)
- [Online Activation By Authorization Code](/docs/fundamental-concepts/how-does-online-activation-work/online-activation-by-authorization-code.md)
- [Offline activation](/docs/fundamental-concepts/how-does-offline-activation-work.md)
- [Offine Activation of License Keys](/docs/fundamental-concepts/how-does-offline-activation-work/offine-activation-of-license-keys.md)
- [Offline activation of License Files](/docs/fundamental-concepts/how-does-offline-activation-work/offline-activation-of-cross-platform-apps-with-license-files.md)
- [Deactivation Verification Code for Offline Deactivation](/docs/fundamental-concepts/how-does-offline-activation-work/deactivation-verification-code-for-offline-deactivation.md)
- [QLM Timer](/docs/fundamental-concepts/qlm-timer.md)
- [Maintenance Plan](/docs/fundamental-concepts/qlm-maintenance-plan.md)
- [How to implement software subscription](/docs/fundamental-concepts/how-to-implement-software-subscription.md)
- [Subscription workflow when integrated with an eCommerce Provider](/docs/fundamental-concepts/subscription-workflow-when-integrated-with-an-ecommerce-provider.md)
- [Check for Updates](/docs/fundamental-concepts/how-does-the-check-for-updates-feature-work.md)
- [License Activation Count](/docs/fundamental-concepts/license-activation-count.md)
- [Organizations](/docs/fundamental-concepts/organizations.md)
- [History log](/docs/fundamental-concepts/qlm-history-log.md)
- [WebHooks](/docs/fundamental-concepts/qlm-webhooks.md)
- [Analytics](/docs/fundamental-concepts/qlm-enterprise-analytics.md)
- [User Groups](/docs/fundamental-concepts/user-groups.md)
- [Product Bundles](/docs/fundamental-concepts/product-bundles.md)
- [Customer User Account](/docs/fundamental-concepts/qlm-customer-user-account.md)
- [Server Error Codes (EServerErrorCode)](/docs/fundamental-concepts/server-error-codes-eservererrorcode.md)
- [.NET 6/7/8/9, .NET Core and .NET Standard Support](/docs/fundamental-concepts/.net-6-7-8-.net-core-and-.net-standard-support.md)