In the early days, most people Just used the Internet to search for information. Today’s Internet is a constantly evolving tool that not only contains an amazing variety of information but that also provides new ways of accessing, interacting, and connecting with people and content. As a result, new terms are constantly appearing. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless and optical networking cosmologies.
Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support email Client/Server Architecture A network architecture in which each computer or process on the network is either a client or a server. Internet server (web server) is a special computer, on which websites are stored. Internet servers make the Internet possible. All of the machines on the Internet are either servers or clients. The machines that provide services to other machines are servers.
And the machines that are used to connect to those services are clients. There are Web servers, e-mail servers, FTP servers and so on serving the needs of Internet users all over the world. When you connect to any website such as Google. Com to read a page, you are a user sitting at a client’s machine. You are accessing the Google’s Web server. The server machine finds the page you requested and sends it to you. Clients that come to a server machine do so with a specific intent, so clients direct their requests to a specific software server running on the server machine.
For example, if you are running a Web browser on your machine, it will want to talk to the Web server on the server machine, not the e- mail server. A server has a static IP address that does not change very often. A home machine that is dialing up through a modem, on the other hand, typically has an IP address assigned by the ISP every time you dial in. That IP address is unique for your session it may be different the next time you dial in. This way, an ISP only needs one IP address for each modem it supports, rather than one for each customer.
Web Client Web client is a computer, on which user actually works. It has web browser to locate, retrieve and display contents on web servers. The user logs onto a client computer which then connects to the server, verifies the user and then allows them access to the files stored on the server that they have permission to access. Web Browser A web browser (commonly referred to as a browser) is a software application for retrieving, presenting and traversing information resources on otherworld Wide Web.
An information resource is identified by a Uniform Resource Identifier (URI/URL) and may be a web page, image, video or other piece of content. Function: The primary purpose of a web browser is to bring information resources to the user (“retrieval” or “fetching”), allowing them to view the information (“display”, “rendering”), and then access other information (“navigation”, “following links”). This process begins when the user inputs a Uniform Resource Locator (URL) into the browser. The prefix of the URL, the Uniform Resource Identifier roller, determines how the URL will be interpreted.
The most commonly used kind of URI starts with http: and identifies a resource to be retrieved over the Hypertext Transfer Protocol (HTTP). 12]Many browsers also support a variety of other prefixes, such as HTTPS: for HTTPS, ftp: for the File Transfer Protocol, and file: for local files. Prefixes that the web browser cannot directly handle are often handed off to another application entirely The major web browsers are Firebox, Google Chrome, Internet Explorer, Opera, and Safari HTML (Hyper Text Mark-up Language) HTML or HyperText Markup Language is the standard markup language used to create web pages.
HTML is written in the form of HTML elements consisting of tags enclosed in angle brackets (like ). HTML tags most commonly come in airs like
Every time the user loads the website, the browser sends the cookie back to the server to notify the website of the user’s previous activity.  Cookies were designed to be a reliable mechanism for websites to remember statutes information (such as items in a shopping cart) or to record the seer’s browsing activity (including clicking particular buttons, logging in, or recording which pages were visited by the user as far back as months or years ago). Cookies can also store passwords and form content a user has previously entered, such as a credit card number or an address.
When a user accesses a website with a cookie function for the first time, a cookie is sent from server to the browser and stored with the browser in the local computer. Later when that user goes back to the same website, the website will recognize the user because of the stored cookie with the user’s information. 6] Other kinds of cookies perform essential functions in the modern web. Perhaps most importantly, authentication cookies are the most common method used by web servers to know whether the user is logged in or not, and which account they are logged in with.
Internet Security Issues Mallard: Mallard, short for malicious software, is any software used to disrupt computer operation, gather sensitive information, or gain access to private computer systems.  It can appear in the form of executable code, scripts, active content, and other software.  ‘Mallard’ is a general term used to refer to a variety of forms of hostile r intrusive software.  The term bawdier is sometimes used, and applied to both true (malicious) mallard and unintentionally harmful software.  Mallard includes computer viruses, worms, Trojan horses, ransomed, spare, Edward, shareware, and other malicious programs.
As of 2011 the majority of active mallard threats were worms or Trojan rather than viruses Examples of Mallard are: Clogging software that reads your keyboard strokes and sends them to a hacker – this is a way to get password and personal information directly from your computer Zombie programs that use your system to send spam emails to others, store illegal mages on your computer or overload websites in an extortion attempt Spy;are programs that collect information about the sites you visit for advertisers. Trojan horses are a method for getting Mallard on to your computer.
They work by concealing themselves in other programs that you might choose to download and run. Hacking In the computer security context, a hacker is someone who seeks and exploits weaknesses in a computer system or computer network. Hackers may be motivated by a multitude of reasons, such as profit, protest, challenge or enjoyment.  The subculture that has evolved around hackers is often referred to as the imputer underground and is now a known community. Hackers like to subvert computer security without permission. They are cyber criminals. This can mean gaining access to a computer across the Internet for illicit purposes.
As a result of hacking, some valuable information may be leaked, is often misused and sometimes also lost. While there are plenty of stories about malicious hackers sabotaging computer systems, infiltrating networks and spreading computer viruses, most hackers are Just curious they want to know all the intricacies of the computer world. Some use their knowledge to help corporations and governments instruct better security measures. Others might use their skills for more unethical endeavors. Security Measures Install a firewall A firewall is a software program or piece of hardware that blocks hackers from entering and using your computer.
Hackers search the Internet the way some telemarketers automatically dial random phone numbers. They send out pings (calls) to thousands of computers and wait for responses. Firewalls prevent your computer from responding to these random calls. A firewall blocks communications to and from sources you don’t permit. This is especially important if you have a high-speed Internet connection, like DSL or cable. Use anti-virus software Anti-virus software protects your computer from viruses that can destroy your data, slow down or crash your computer, or allow spammed to send email through your account.
Anti-virus protection scans your computer and your incoming email for viruses, and then deletes them. You must keep your anti-virus software updated to cope with the latest “bugs” circulating the Internet. Most anti-virus software includes a feature to download updates automatically when you are online. In addition, make sure that the software is continually running and checking your system for viruses, specially if you are downloading files from the Web or checking your email.
Use a strong password – and keep it to yourself Protect your computer from intruders by choosing passwords that are hard to guess. Use strong passwords with at least eight characters, a combination of letters, numbers and special characters. Don’t use a word that can easily be found in a dictionary. Some hackers use programs that can try every word in the dictionary. Try using a phrase to help you remember your password, using the first letter of each word in the phrase. For example, [email protected] Be careful if you share files
Many consumers enjoy sharing digital files, such as music, movies, photos, and software. File-sharing software that connects your computer to a network of computers is often available for free. File-sharing can pose several risks. When connected to a file-sharing network, you may allow others to copy files you didn’t intend to share. You might download a virus or bit of spare that makes your computer vulnerable to hackers. You might also break the law by downloading material that is copyright protected. Resources: wry. Intercessory. Org www. Informatics. Buzzed. Com www. Interpenetrates 01 . Org/