Chapter 2 addressed the characteristics of Web Sites, Web Pages, and Web Servers. The Web consists of millions of Web sites and billions of Web pages. It is impossible to determine at any given time the exact number of pages or sites because sites and pages are constantly being added and removed.
The number of pages on a website varies depending upon its use. If it is a personal website, generally there are very few pages. Business websites can include many pages. A home page is the first page you see of a website. Websites with multiple pages are linked together so that people can easily navigate their way through the site.
A web portal is a website that is a funnel to a wide range of content. Google, Yahoo, AOL, and MSN are examples of portals. When an individual opens their browser, a web portal provides the starting point for their search activities. There are general interest portals as well as portals that are used for special interests.
IP addresses, domain names and URLs are used to locate a specific website. An IP address is a number that identifies a specific computer connected to the Internet. Because IP addresses are difficult for people to remember, domain names were developed. A domain name is a text name for an IP address that is easier for people to remember. It was first invented by Paul Mockapetris in 1983. In 1984, four Berkley students made revisions to enable domain names to run on Unix systems. This was referred to as BIND and is the dominant domain name software (DNS) in use on the Internet today.
Web pages also have URLs which stands for Uniform Resource Locator. A URL is a web address that contains the protocol and the name of the server hosting the Web page.
A Web browser is used to locate and access a specific Web site. Frequently used browsers for personal computers are Firefox, Safari, Google and Internet Explorer.
When you surf the net, you are accessing information stored on servers located all over the world. This very public arena connects millions of computers and people. Although there are many positive benefits to this, there are risks which include hackers and viruses. A hacker is a person who uses his computer skills to gain access to a network without authorization. Once into the network the hacker can access data and programs, save, and manipulate files. Recently in the news we've heard a great deal about the Chinese government hacking into the computer networks of major US technical companies such as Apple. Something I didn't realize is that your computer network is at greater risk if you connect to the internet using DSL or cable Internet connections. You can establish a firewall to protect your network from hackers. A firewall examines the network connection to warn you if an unauthorized person is trying to access your network or it can prevent incoming communications from an unknown computer.
Virus protection software can protect your computer from viruses. These are software programs that are installed on your computer from software development companies such as Norton and McAfee. The most likely way that your computer can be infected with a virus is through email communications. Viruses are embedded in email attachments and once opened, infect your computer. You should always avoid opening email and attachments that are received from unknown sources. When shopping online, it is best to shop on the sites of large, well-known companies. This provides better reassurance that your transaction information will be handled properly. An example of a large, well-established online merchant is Amazon.
Another Internet issue is objectionable or inappropriate content. This is especially important for parents of children who often use their computer to search the web or use web-based information for homework. Content can be filtered using content filters such as iPrism, McAfee SmartFilter, and Net Nanny.
No comments:
Post a Comment