Execution Context

Let's understand the Execution Context in JS.

an execution context is a abstract concept that refers to the environment in which the JavaScript code is executed. It's the scope in which the code is running, and it provides the necessary information for the JavaScript engine to execute the code correctly.

When is an Execution Context Created?

An execution context is created in the following scenarios:

• When the JavaScript engine starts executing a script (e.g., when a web page loads)
• When a function is called
• When a setTimeout() or setInterval() function is triggered
• When an event handler is triggered (e.g. when a user clicks a button)

The execution context in JavaScript can be broken down into two main components: the Memory Component and the Code Component.

Memory Component (Variable Environment)

• Stores variables and functions in key-value pairs
• Holds data and functions in scope

Code Component (Thread of Execution)

• Executes code one line at a time
• Follows a specific order

JavaScript is:

• Synchronous: Executes code in a specific order
• Single-threaded: Executes one line of code at a time

Conclusion :

The execution context is essential for JavaScript code execution, providing the necessary environment and following a specific order?. Understanding its components and creation scenarios will improve your coding skills?. Happy coding!?

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