String concatenation in JavaScript

We use the operator + to concatenate strings, as well as to add numbers:

let str = 'abc' + 'def'; // add two strings alert(str); // shows 'abcdef'

Strings can also be stored in variables:

let str1 = 'abc'; let str2 = 'def'; alert(str1 + str2); // shows 'abcdef'

You can also add variables with strings:

let str1 = 'abc'; let str2 = 'def'; alert(str1 + '!!!' + str2); // shows 'abc!!!def'

Let two strings are stored in variables, and we want to insert a space between them when we add them. It's done like this:

let str1 = 'abc'; let str2 = 'def'; alert(str1 + ' ' + str2); // shows 'abc def'

Let there be only one variable:

let str = 'abc'; alert(str + ' ' + 'def'); // shows 'abc def'

In this case, it makes no sense to arrange the space in the separate string - we will insert it as part of the second term:

let str = 'abc'; alert(str + ' def'); // shows 'abc def'

Create the variable str and assign the string '!!!' to it. Display the value of this variable on the screen.

Create the variable with the text 'java' and variable with the text 'script'. Using these variables and the string concatenation operation, display the string 'javascript' on the screen.

Create the variable with the text 'hello' and variable with the text 'world'. Display the string 'hello world', using these variables and the string concatenation operation.

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