How do programming languages have syntax?

In JavaScript, which is one of the popular programming languages, there is a specific syntax for declaring a variable. Here is an example of the syntax for declaring a variable in JavaScript: ```javascript let userName = "John Doe"; ``` In this example, `let` is the keyword for declaring a variable, `userName` is the name of the variable, and it is assigned a value "John Doe" using the equal sign (=). Now I will give you two examples of syntax from Python, another widely used programming language: 1. Defining a function in Python: ```python def greet(name): return f"Hello, {name}!" ``` Here, `def` is the keyword used for defining a function, `greet` is the name of the function, and `(name)` represents the input parameter that the function takes. The colon (:) indicates the start of the function body, which is indented to the right. 2. Using conditional statements in Python: ```python age = 18 if age >= 18: print("You are eligible to vote.") else: print("You are not eligible to vote yet.") ``` In this example, `if` is the keyword for a conditional statement, followed by a condition `age >= 18`. The colon (:) indicates the start of the block that will run if the condition is true. After that, we use the `else` keyword for the alternative condition, again followed by a colon (:) and indented block for the code to run if the initial condition is not met. If you do not follow the syntax rules in Python or any other programming language, the program will not work, and you will likely get an error. The error messages will provide some information about the issue, so you can find and fix the problem in your code. Errors due to incorrect syntax are called "syntax errors."