String Index.

Text chapter. Foundations showed template literals; Data showed arrays. Now the string is the main character: a sequence of characters.

Every character has an index starting at 0. The first is text[0], the second text[1]. Length is text.length (a number). The last character is often text[text.length - 1].

Square brackets read one character. This goes deeper than “just glue text together” from Foundations.

Mini example:

const tag = "food"; console.log(tag[0]); console.log(tag.length); console.log(tag[tag.length - 1]);

Common mistake: expecting text[1] to be the first character; or confusing length with the last index (length is the count; the last index is length - 1).