Showing Revision 3 created 05/25/2016 by Udacity Robot.

1. Title:
   Cookie Headers - Web Development
2. Description:

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   Okay. So I alluded to this before. Cookies are sent
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   in HTTP headers. So when a server and, and an HTTP
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   response, wants to give you a cookie, wants to assign a
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   cookie to your browser it uses a header that looks something
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   like this. The header name is Set-Cookie. Like all headers, it's
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   followed by a colon and then a space and then the
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   value of the header. And in this particular case, you say,
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    name equals value. There are some other parameters you can have
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    on the cookie that we'll discuss later but, basically, they use
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    the Set-Cookie header to, to set cookie named user_id to this
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    value. And remember, this is the value, and this is the
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    name, and the value can be, you know, up to 4K.
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    Honestly, I don't know if there's a limit to how big
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    the name can be. generally, this is very, very short. If
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    the server wants to set, send the multiple cookies, it can
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    do so by using multiple Set-Cookie, Cookie headers. There's no restriction
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    that says headers have to be unique. A, a server can
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    send as many cookies as it wants. It's up to the browser
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    to decide whether or not to store them. Remember, I said about
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    20 is the max. So try to, try to keep it under
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    there. Now, when, when a, this is under Response. Now, in
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    future requests, the browser sends its own header, that this is the,
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    the name of the header, and remember, this is, you know, this
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    is also the name of the header, over here, Set-Cookie and then
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    the value of the header, in this case, is user_id
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    equals 12345. Again, we have the, the name of the
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    cookie and the value of the cookie. If we were
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    to make this H, this request match what these two cookies
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    were to, when our browser sends multiple cookies, it'll look
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    something like this, user_id equals 12345; which separates each cookie from
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    each other, and then any other cookies. So the browser
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    sends one cookie header with all of your cookies in it.
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    The semicolon is important and you may be wondering, well, what
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    if I want to put a semicolon in my cookie value? And the
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    short answer is, don't. And if you really want to, encode
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    the cookie value, you know? You, this, this can be whatever you
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    want. The browser doesn't care so you can, you can Base64
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    it, you can encrypt it, you can ROT13 it, you can do
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    whatever you want here but make sure you escape those semicolons
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    so you don't goof up your the incoming cookie header. Some frameworks
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    will do this for you. We are going to be operating
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    at a lower level so that's something you'll want to think about.