[Home](./index.md) > [puppeteer](./puppeteer.md) > [ExecutionContext](./puppeteer.executioncontext.md) ## ExecutionContext class This class represents a context for JavaScript execution. A \[Page\] might have many execution contexts: - each [frame](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe) has "default" execution context that is always created after frame is attached to DOM. This context is returned by the [Frame.executionContext()](./puppeteer.frame.executioncontext.md) method. - [Extension](https://developer.chrome.com/extensions)'s content scripts create additional execution contexts. Besides pages, execution contexts can be found in [workers](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API). Signature: ```typescript export declare class ExecutionContext ``` ## Remarks The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the `ExecutionContext` class. ## Methods | Method | Modifiers | Description | | --- | --- | --- | | [evaluate(pageFunction, args)](./puppeteer.executioncontext.evaluate.md) | | | | [evaluateHandle(pageFunction, args)](./puppeteer.executioncontext.evaluatehandle.md) | | | | [frame()](./puppeteer.executioncontext.frame.md) | | | | [queryObjects(prototypeHandle)](./puppeteer.executioncontext.queryobjects.md) | | This method iterates the JavaScript heap and finds all the objects with the given prototype. |