Known formally as Universal Resource Locators, URLs tell the requestors like servers and browsers where to find a page.

The diagram above illustrates the different pieces of a URL’s anatomy.

Friendly URLs contain words instead of long lists of numbers and letters.

They are desirable because they are human readable, and for the small keyword relevance signal they send to search engines.

Consider, for example, the following two URLs.

Alphanumeric characters are important because any character that is not 123 or abc or one of the few allowed punctuation marks (such as ?

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