> For the complete documentation index, see [llms.txt](https://lochiwei.gitbook.io/web/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://lochiwei.gitbook.io/web/js/concept.md).

# concept

[JS](/web/js.md) ⟩ concepts

{% tabs %}
{% tab title="🔴 主題" %}

* [compilation](/web/js/compile.md)
  * [statically typed](/web/js/val/type/term/static.md) vs. [dynamically typed](/web/js/val/type/term/dynamic.md)
  * [runtime](/web/js/compile/runtime.md) vs. [compile-time](/web/js/compile/compile-time.md)
  * [grammar](/web/js/grammar.md)
  * [scope](/web/js/scope.md) - <mark style="color:green;"><mark style="color:yellow;">**visibility**<mark style="color:yellow;"></mark> of [variable](/web/js/variable.md).
* [value](/web/js/val.md)
* [variable](/web/js/variable.md)
* [expression](/web/js/grammar/statement/expr.md)
* [context](/web/js/concept/context.md) - [this](/web/js/concept/execution-context/this.md) <mark style="color:yellow;">**object**</mark> to which a [function](/web/js/val/func.md) refers.
  * [context vs. scope](/web/js/scope/context-vs.-scope.md)
* [environment](/web/js/concept/env.md)
  {% endtab %}
  {% endtabs %}