Hello, Out Loud

What console.log does

A program tells you nothing unless you ask it to. In JavaScript, console.log is how you ask.

Whatever you put between the round brackets of console.log(...) gets shown on the screen. Wrap it in quotes and JavaScript treats it as plain text, showing it exactly as written — letters, spaces, punctuation and all.

The name is two words with a dot between them, and both halves mean something. console is the panel your words come out on. log is what you are asking it to do there: write this down. You will type the pair together more times than you can count, so it is worth reading it once as two ideas rather than as one long word.

Two smaller things are part of the line rather than decoration:

• The quotes are what make text. "Priya" is a name spelled out; Priya with no quotes around it would be something JavaScript goes off looking for.
• The semicolon on the end says that instruction is finished. JavaScript will often work that out on its own from the line break, but every instruction in this editor ends with one, and the habit costs nothing.

A worked example

Here is a different program, so the one in the editor stays yours to finish:

console.log("step 1: fill the kettle");
console.log("step 2: wait");
console.log("step 3: pour");

Running that prints three lines:

step 1: fill the kettle
step 2: wait
step 3: pour

Three calls to console.log, three lines of output, in the order they were written. Each call starts a new line of its own — you never have to ask for one. Notice too that the numbers, the colons and the spaces come out exactly as they were typed. JavaScript did not tidy anything up or add anything of its own.

Your turn

The editor already holds a working program. Press Run before you change anything and you will see a banner: a row of = signs, two lines of text, then another row of = signs.

One thing is wrong with it. The second line says YOUR NAME where your name belongs.

Type your own name over those two words, keep the quotes exactly where they are, and press Run again.

That is the whole task. You are not expected to write a line from scratch yet.

If something goes wrong

If JavaScript complains, it is almost always the quotes. The text you want on screen has to sit between them. "Hello, Ravi!" works; Hello, Ravi! on its own does not, and you get a SyntaxError about a bracket, because JavaScript was trying to read your name as part of an instruction and the sentence stopped making sense.

The other likely slip is a capital letter. Console.log is not console.log, and JavaScript says so plainly: ReferenceError: Console is not defined. It means it looked for something by that name and found nothing.

Nothing you do here can break anything. Your code stays in this browser, so a half-finished attempt is still here if you come back to it, and nothing is sent anywhere. Change it, run it, change it again.