message: docs: add change detection to glossary
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diff: @@ -144,6 +144,23 @@ For example, "convert_link_mode".
  * UPPER_UNDERSCORE_CASE (or UPPER_SNAKE_CASE, or SCREAMING_SNAKE_CASE): Traditional for constants (acceptable, but prefer camelCase).
  Upper snake case uses words in all capital letters connected with underscores. For example, "FIX_ME".
  +{@a change-detection}
  +
  +## change detection
  +
  +The mechanism by which the Angular framework synchronizes the state of an application's UI with the state of the data.
  +The change detector checks the current state of the data model whenever it runs, and maintains it as the previous state to compare on the next iteration.
  +
  +As the application logic updates component data, values that are bound to DOM properties in the view can change.
  +The change detector is responsible for updating the view to reflect the current data model.
  +Similarly, the user can interact with the UI, causing events that change the state of the data model.
  +These events can trigger change detection.
  +
  +Using the default ("CheckAlways") change-detection strategy, the change detector goes through the [view hierarchy](#view-tree) on each VM turn to check every [data-bound property](#data-binding) in the template. In the first phase, it compares the current state of the dependent data with the previous state, and collects changes.
  +In the second phase, it updates the page DOM to reflect any new data values.
  +
  +If you set the `OnPush` ("CheckOnce") change-detection strategy, the change detector runs only when [explicitly invoked] (api/core/ChangeDetectorRef), or when it is triggered by an `Input` reference change or event handler. This typically improves performance. For more information, see [Optimize Angular's change detection](https://web.dev/faster-angular-change-detection/).
  +
  {@a class-decorator}
  ## class decorator
  @@ -938,7 +955,7 @@ View hierarchies can be loaded and unloaded dynamically as the user navigates th
  ## view hierarchy
  -A tree of related views that can be acted on as a unit. The root view is a component's *host view*. A host view can be the root of a tree of *embedded views*, collected in a *view container* (`ViewContainerRef`) attached to an anchor element in the hosting component. The view hierarchy is a key part of Angular change detection.
  +A tree of related views that can be acted on as a unit. The root view is a component's *host view*. A host view can be the root of a tree of *embedded views*, collected in a *view container* (`ViewContainerRef`) attached to an anchor element in the hosting component. The view hierarchy is a key part of Angular [change detection](#change-detection).
  The view hierarchy doesn't imply a component hierarchy. Views that are embedded in the context of a particular hierarchy can be host views of other components. Those components can be in the same NgModule as the hosting component, or belong to other NgModules.
  