What does the ^ symbol do in a regular expression?

In a regular expression, the ^ symbol is used to indicate the start of a string. It asserts that the following pattern must occur at the beginning of the string being tested.

For example, in the regex pattern ^abc, it will match any string that starts with "abc". If the string is "abcdef", it will match, but if the string is "xyzabc", it will not match because "abc" does not appear at the start of the string.

Here's a quick example in JavaScript:

const regex = /^hello/;
console.log(regex.test("hello world")); // true
console.log(regex.test("say hello")); // false

In this example, the regex checks if the string starts with "hello".