2.3 Internet Principles of Operation

Provides access to the internet, usually for a fee. Customers need to follow the ISP's terms of service, which may include data download limits and legal regulations. ISPs may also allow users to personalize their internet access, such as setting filters.

Used to access web pages. It translates the website's URL (Uniform Resource Locator) entered by the user into the server's IP address, downloads and displays the page content, and allows users to navigate to other pages via hyperlinks.

Stores website pages and content and handles requests from clients. Downloading is when the client retrieves information from the server, and uploading is when the client sends information to the server. Powerful servers are used to host popular websites, but they may crash if there are too many requests (like when tickets for events are released online). They can also be attacked by Distributed Denial of Service (DDOS) attacks.

Hypertext Transfer Protocol (http) is used for data transmission on the internet and is a request - response protocol, but it is not secure. Https is a secure version used for applications like banking and shopping that need to protect personal information. Transmission Control Protocol (TCP) handles the transfer of data and ensures it is error - free. HTML is the language used to write web pages. It consists of content and display instructions (markups). Markups are in the form of tags, like <b> for bold text, <h1> for a large font heading, <a> for defining a hyperlink, and <p> for setting a new paragraph. Hypertext contains hyperlinks that allow users to access other related resources. Cascading Style Sheets (CSS) separate the content and structure of a web page from its presentation, making it easier to update the look of a website. HTML documents have a structure including a header (declaring the document type, page title, and other instructions) and a body (containing the content, hyperlinks, and formatting instructions if no CSS is used).

IP addresses are used to identify devices on a network. IPv4 addresses are 32 - bit and divided into 4 groups (each ranging from 0 - 255). IPv6 addresses are 128 - bit. Devices can have static or dynamic IP addresses. Uniform Resource Locator (URL) is the website address, consisting of the access protocol (http or https) and the domain name. It is easier for users to remember than the IP address and is translated into the IP address by a domain name server. Media Access Control (MAC) address is a unique identifier for network devices, assigned by the manufacturer and cannot be changed. It is a 48 - bit binary code represented as six pairs of two - digit hexadecimal numbers. Cookies are small pieces of data downloaded by a computer when visiting a website. They are stored by the browser and used to track user login status, shopping cart contents, etc. However, some cookies are used for tracking user activities or storing sensitive information, and users can choose to decline or delete them.