What is hyper text?
Hyper-text is the text that contains links (called as hyperlinks) which can navigate us from one web page to another web page. And you know, why do we need to navigate from one page to the other.HTML (Hyper-text markup language) is a language that is used to develop pages with hyper text. And HTTP is the protocol that is responsible for the transfer of these pages from server to the client.
Both HTTP protocol and HTML, World-Wide-Web are invented by Tim-Berners Lee with his team.
What is a protocol and HTTP protocol?
A protocol is a set of rules or simply a program. A HTTP protocol defines how data should be transferred from client to the server. It contains commands for establishing the connection to the server, sending the user data to the server, downloading the web page.HTTPS is another protocol similar to HTTP but, the data sent/received to/from the server is encrypted before transferred. This is slower, because there is an intermediate process called encryption. This is used while transferring sensitive information like usernames and passwords. That is why most login pages have https connection.
Statelessness of HTTP protocol
The HTTP protocol is responsible for the sending of request and receiving of response, once this process is complete (i.e. one-request-and-the-response-for-it), the http protocol forgets about the data transferred with the request and the data received in the response. This is why http is a stateless protocol.
One-request-and-the-response-for-it is called as a transaction. So don't get stumped, when you are hit with the word transaction.
Static vs dynamic pages
A web page contains information that is stored in a server. There are two types of web pages static and dynamic.
Static web pages: These pages contains just the information and probably some links to navigate to other pages. The information in these pages is written by someone and stored in the server as a file. The only use of these pages is to just read the information present in them. Best example, is this page, where you just read information which doesn't change by your action.
Dynamic web pages: These pages also contains information, but the information in these pages will change according to the user input. Best example, is Google search, where based upon your search query, you get the results page.
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