Null

“Null” represents the absence of a value or the presence of invalid objects in computer science and web development. It indicates when a variable or object contains no data or if a function does not return a value, preventing errors and unexpected element behavior by signaling when a value, object, or function is missing or invalid.

In programming languages like JavaScript, “null” shows that a specific element has no assigned value, rather than having a value of zero, an empty string, or any other data you may interpret as valid.

For example, a variable called result stores a specific calculation's output. If the calculation fails or produces an invalid result, you can assign a null value to the variable with this code snippet:

let result = null;

The output indicates the variable has no assigned value, informing other parts of the program that the result needs replacing before use.