How People Access the Web

BROWSERS

• People access websites using software called a web browser.
• Ex: Internet Explorer, Chrome, Firefox, Safari, and Opera

  WEB SERVERS

• When you ask your browser for a web page, the request is sent across the Internet to a special computer known as a web server which hosts the website.
• Some big companies run their own web servers, but it is more common to use the services of a web hosting company who charge a fee to host your site.

  DEVICES

• People aceess websites on an increasing range of devices including desktop computers, laptops, tablets, and mobile phones.

  SCREEN READERS

• Screen readers are programs that read out the contents of a computer screen to a user.

  How Websites Are Created

  WHAT YOU SEE

• When you look at a website, your browser will receive HTML and CSS from then web server that hosts the site.
• The web browser interprets the HTML and CSS code to create the page that you see.
• Most web pages also include extra content such as images, audio, video, or animations.

  How It Is Created

• Small websites are often written just using HTML and CSS.
• Larger websites often make use of more complex technologies on the web server.
• Larger, more complex sites may use a database to store data, and programming languages suchs as PHP, ASP.NET, Java, or Ruby on the web server.

  HTML5 & CSS3

• Since the web was first created there have been several versions of HTML and CSS.

How the Web Works

• When you visit a website, the web server hosting that site could be anywhere in the world.
• In order for you to find the location of the web server, your browser will first connect to a Domain Name System (DNS) server.
  1. When you connect to the web, you do so via an Internet Service Provider (ISP). You type a domain name or web address into your browser to visit a site.
  2. Your computer contacts a network of server called Domain Name System (DNS) server. Every device on the web has a unique IP address.
  3. The unique number that the DNS server returns to your cmoputer allows your browser to contact the web server that host the website you requested.
  4. The web server then sends the page you requested back to your web browser.