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Building a Case for HTTP

2:41 with Unsubscribed User

The internet consists of a vast array of highly-connected devices spanning the entire globe. To ensure that any two devices can communicate, it was necessary to develop a common set of rules - or protocol - to facilitate dependable communication.

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    Now you might be asking yourself, why do we need a set of rules for

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    two devices to talk to each other?

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    Aren't rules limiting?

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    Well, think about the way we hold phone conversations with family or friends.

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    The nature of your conversations probably varies widely from making dinner plans to

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    expressing sympathy from a loss, to catching up after a year or

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    two of losing touch.

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    However, all of these conversations probably follow a set of conventions.

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    First, there's some sort of greeting.

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    Hello?

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    Hi Courtney, this is Chris.

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    Or some variation of that.

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    What follows is a series of comments and sequence.

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    As in, one person talks, then the other, but

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    never at the same time where neither person is heard by the other.

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    And if a question is asked, well, a response quickly follows.

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    Unless there's no response, which can be unexpected or just plain awkward.

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    Both people know the conversation is over when each person says, goodbye or

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    talk to you soon.

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    Communication between devices over the internet is not

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    unlike spoken language over the phone.

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    Except that there are even more rules, to make sure machines don't end up

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    guessing what question was asked or what answer was given.

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    You might equate this rigid communication environment to a court room.

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    Where the judge won't response to an attorney shouting, hey or

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    no you didn't, but would respond to a simple objection.

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    Likewise, in internet communication word choice matters.

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    If the internet was going to be successful,

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    it required a set of standards for device communication.

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    That is, communication between the devices that contain the information and

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    the devices that wish to interact with it.

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    So, when Tim Berners-Lee and his team proposed the World Wide Web project

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    in 1989, what soon followed was the first published version of HTTP.

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    This was HTTP 0.9 in 1991.

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    The HyperText Transfer Protocol is the setup rules that

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    governs the messaging between devices over the Internet.

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    It functions mainly as a request-response cycle between a client and a server.

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    That is, a client makes a request and a server responds.

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    Examples of clients are a web browser, such as Chrome or Safari,

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    a native mobile app on iOS or Android like the Facebook app on your phone.

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    Or even a in a desktop weather application like one written in JavaFX.

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    The main example of a server is a web server such as Apache,

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    Nginx and Node.js server or even a Java enabled web server like Tomcat.

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    After a quick break let's see HTTP in action

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    using a simple text-based tool called Telnet.

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