Question

Subject Javascript:

Before HTML5, websites could store only small amounts of text-based information on a user's computer using cookies. What are the advantages of using cookies and why are they so important as it pertains to web applications?

Answer 1

Cookie:- A cookie is basically an amount of information that persists between a server and a client . A web browser used to stores this information when we are browsing anything on web browser.

Generally cookie contains the information in the form of a name-value pair separated by semi-colons.

Cookies used to maintains the state of a user and cookie used to remembers the user's information among all the web pages.

JavaScript can also manipulate cookies using the cookie property of the Document object. JavaScript can read, create, modify, and delete the cookies that apply to the current web page

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web Browser Server

-------------------------Request-------------------------->>

< <-----------------------Response+Cookie----------------

-------------------------Request+Cookie-------------------->

• When a user sends a request to the server, then request is treated as a new request sent by a different user.
• So, to recognize the old user, we need to add the cookie with the response from the server to the browser at the client-side.
• whenever a user sends a request to the server, the cookie is added with that request from client machine. Due to the cookie, the server recognizes the users.

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Basically two type of cookies

Non-persistent cookie :- It is valid for only single session and removed each time when user closes the browser.

Persistent cookie :-It is valid for multiple session and removed only if user logout from the website.

Advantage of Cookies

1. Easy and simple technique of maintaining the state.
2. Cookies are maintained at client side not on server side.
3. cookie must be enabled in client machine.
4. We can set textual information in Cookie object.

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why are they so important as it pertains to web applications?

Cookies are widely used in order to make websites work, or work more efficiently, as well as to provide information to the owners of the Website

users session information:-It is required to maintain session information among different pages for any website .Example - Let suppose ,One user is doing registration and its ends after completing many pages. But how to maintain users session information across all the web pages in website.

Better visitor experience or website statistics:-In many situations, using cookies is the most efficient method of remembering and tracking preferences, purchases,and other information required for better visitor experience or site statistics.

HTML 5 uses SQL databases and application cache to store offline data basically