The web 2.0 is a phrase which was first used in by a company called “O’Reilly Media” to define a new version of the World Wide Web, its main characteristics were:

1- It made the WWW public, generating and distributing web content began to be more common, users could participate in the sites data creation and create their own pages, threads, blogs, videos and auctions. These sites such as Wikipedia, Ebay, and Youtube have now become the leaders on the WWW and contain big usercommunities which update their sites data consistently.

2- Categorization and organization of content, such as the deep linking, site owners organized their content in a more comfortable, user freindly way using the back slash (/). The sites appeared more clear on search engines and the user could just type www.site.com/news instead of browsing the whole site to find this section.

3- And the last, most important thing was the “Dot-Com boom” , in which many new Internet-based companies began their work as their owners saw their potential on the Internet, companies such as Google and Ebay had been founded in the early beginning of the “boom” and became the great success of today.

The uses of Web 2.0

Web-based applications and desktops:

These “online desktops” are similar to a PC environment and function as application platforms giving the user the feeling his is at his desktop, not online, today this service is mostly used when a user wants to enter his desktop from another computer, all he/she needs to do is to sign up to one of these services and the problem is fixed.

Rich Internet applications:

Client-side software

Web 2.0 gives the users an option to work with data stored on servers, a simple example of it is an online html form which can be found anywhere these days, this forms are made using the scripting languages such as javascript, Java or flash, the forms are very helpful for site owners who can easily browse the form with all the details included inside and sort it or make further uses out of it (such as export it and store it on a side-server).

XML

XML is a fee-free open standard. Its primary purpose is to facilitate the sharing of data across the Internet. XHTML and RSS are written on the XML language by adding semantic constraints.

RSS

The RSS is another Web 2.0 feature giving the users an option to make other uses of a sites data.
The RSS is used to publish content updates such as new headlines on news sites or blog entries.
The user can enter and see the updates made on his chosen site and the chosen section (News/Music/Jokes) without
the need to search for them by himself.

Web protocols

Web communication protocols are supported by the Web 2.0 structure. These protocols such as the REST and SOAP involve some form of XML coding in them.