(More precisely, the expression that you type consists of the numerals that represent the number in base 10.) If you ask our script to evaluate the expression statement
486;

by clicking it, it will respond by creating a separate browser tab where the statement is shown, with the option to evaluate the statement by pressing a Run button. Click on the primitive expression statement, and see what happens!
[1] JavaScript follows its precursor Lisp by obeying the convention that every statement has a value. This convention, together with the old reputation of Lisp as an inefficient language, is the source of the quip by Alan Perlis (paraphrasing Oscar Wilde) that Lisp programmers know the value of everything but the cost of nothing.
1.1.1 Expressions