Why should a Bearer be added to the Authorization header for API authorization?

When designing API authorization, or calling third-party APIs, you often come into contact with:

Authorization : Bearer Tokenxxxxxx

Do you have any doubts about why not just write it like this:

Authorization : Tokenxxxxxx

This is because of W3C's HTTP 1.0 specification, the format of Authorization is:

Authorization: <type> <authorization-parameters>

So Bearer is the type of authorization. Common types of authorization include:

• Basic for http-basic authentication;
• Bearer is commonly used in OAuth and JWT authorization;
• http-basic authentication with Digest MD5 hash (DEPRECATED)
• AWS4-HMAC-SHA256 AWS authorization
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