Q. The expression of calling ( or executing ) a function or method in JavaScript is called

Explanation by: Praveen Singh

In JavaScript, invocation expressions are used to call or execute a function or method. When you write an expression like myFunction(), you're invoking or executing the function named myFunction.
Let's break down the concept:
Expression: In programming, an expression is any valid combination of variables, constants, operators, and functions that can be evaluated to produce a value.
Invocation Expression: An invocation expression specifically refers to the act of calling or invoking a function. It involves using parentheses () to trigger the function or method to execute its code.
For example:
function greet(name) {
    console.log("Hello, " + name);
}

greet("Alice");  // This is an invocation expression
Here, greet("Alice") is an invocation expression, which calls the greet function and passes "Alice" as an argument.
Key Points:
Function invocation: When you use () after a function name, you're invoking the function.
Execution: The function code runs only when it's invoked.
In contrast, other types of expressions include:
Property Access Expression: Accessing a property of an object, e.g., obj.property.
Functional Expression: This refers to expressions that define functions (e.g., a function declaration or function expression).
Primary Expression: Refers to basic expressions like variables or literals, e.g., 5, "Hello", or x.
Thus, an invocation expression is specifically about calling a function or method to perform an action or return a result.