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JavaScript: Naming a variable

Imagine the code from the previous lesson looks like this:

let x = 'Father!';

Although it works, the variable name is now x. A computer doesn't care about naming since it's a mindless machine, but developers do care. We are mostly read someone else's code, then write or read our own. Quality and clarity of variable names is half the battle when it comes to code analysis.

It's best take a moment and come up with a name reflecting the essence and meaning of the variable than give it a random name and rename it later. Try to name variables to make them as comprehensive as possible without context, or without examining the surrounding code.

A common joke among developers is that "the hardest part of programming is cache invalidation and naming things". Coming up with names is tough indeed. How would you name a variable that stores the number of unpaid orders from customers in debt from the previous quarter?

const firstName = 'John';
console.log(firstName); // => John

const playerNumber = 24;
console.log(playerNumber); // => 24

Self-сheck. Think of a name for the variable that would store "the number of siblings the king has". Write it down in a notebook or send it to yourself. Don't put anything in there except the name of the variable. And we'll come back to this topic in a few lessons ;-)


Create a variable storing the number of my brothers and assign it a value of 2. Print it. After completing the tests, compare your name with the teacher's variable name in the solution.

The exercise doesn't pass checking. What to do? 😶

If you've reached a deadlock it's time to ask your question in the «Discussions». How ask a question correctly:

  • Be sure to attach the test output, without it it's almost impossible to figure out what went wrong, even if you show your code. It's complicated for developers to execute code in their heads, but having a mistake before their eyes most probably will be helpful.
In my environment the code works, but not here 🤨

Tests are designed so that they test the solution in different ways and against different data. Often the solution works with one kind of input data but doesn't work with others. Check the «Tests» tab to figure this out, you can find hints at the error output.

My code is different from the teacher's one 🤔

It's fine. 🙆 One task in programming can be solved in many different ways. If your code passed all tests, it complies with the task conditions.

In some rare cases, the solution may be adjusted to the tests, but this can be seen immediately.

I've read the lessons but nothing is clear 🙄

It's hard to make educational materials that will suit everyone. We do our best but there is always something to improve. If you see a material that is not clear to you, describe the problem in “Discussions”. It will be great if you'll write unclear points in the question form. Usually, we need a few days for corrections.

By the way, you can participate in courses improvement. There is a link below to the lessons course code which you can edit right in your browser.


If you got stuck and don't know what to do, you can ask a question in our community