The World Wide Web

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Internet is a global network of networks defined by a set of open standards for communicating data and information among computers. The World Wide Web is an Internet client-server hypertext distributed information retrieval system, which originated from CERN laboratory in Switzerland.

Fast-Growing Web

The publicly indexable Web contained at least 5.28 billion webpages and almost 2 billion websites operated as of November 2018. It is added more than one million pages everyday. About 74% of servers contain commercial content. The remaining contents are shown on the right. (The data may not be valid because of the recent surge in social networks.)

HTTP (HyperText Transfer Protocol)

It is the method used to transfer hypertext files across the Internet. On the Web, pages written in HTML use hypertext to link to other documents. When you click on hypertext, you jump to another page, file, or image.

HTTPS (HTTP Secure)

When a user connects to a website via HTTPS, the website encrypts the session with a digital certificate. To do this, the computer at each end uses a document called an “SSL (Secure Sockets Layer) Certificate” containing character strings that are the public keys to their secret “codes.” The owner shares the public key with anyone who needs it and other users need the public key to encrypt messages to the owner. However, the owner does not share the private key.