What is HTTP

HTTP stands for Hypertext Transfer Protocol. It's a protocol used for transferring hypertext requests and information between servers and browsers - essentially, it's the protocol that enables the functioning of the World Wide Web.

Here's a more detailed breakdown of the components:

• Hypertext
  This is structured text that uses logical links (hyperlinks) between nodes containing text. In simpler terms, it's a way of connecting pieces of information together, which is how web pages are connected via links.

• Transfer
  This refers to the process of moving or transmitting something from one place to another. In the context of HTTP, it's about transferring hypertext (and other data) over a network.

• Protocol
  A protocol is a set of rules or procedures for transmitting data between electronic devices, such as computers. It's essentially the 'language' that computers use to communicate.

When you type a URL into your web browser, an HTTP command is sent to the Web server directing it to fetch and transmit the requested Web page. The other main standard that controls how the World Wide Web works is HTML, which covers how Web pages are formatted and displayed.

HTTP is a stateless protocol, meaning it doesn't store any data between two requests. However, with the introduction of HTTP cookies, it can "remember" information between sessions.

How HTTP Works

HTTP is an application-layer protocol that uses a client-server model, where the client (usually a web browser) sends requests to a server hosting a website or web application. The server processes the request and sends back an appropriate response.

The communication process in HTTP typically follows these steps:

1. The client opens a connection to the server using its IP address or domain name.
2. The client sends an HTTP request to the server, containing information about the desired resource and any additional data required.
3. The server processes the request and generates an HTTP response, containing the requested resource or an appropriate status code.
4. The server sends the response back to the client.
5. The client processes the response, rendering the content if the request was successful or displaying an error message if it failed.

What is HTTPS

HTTPS stands for Hypertext Transfer Protocol Secure. It is the secure version of HTTP, the protocol over which data is sent between your browser and the website that you are connected to.

When a website is accessed over HTTPS, the URL will start with https:// and a padlock icon is typically displayed in the address bar of most browsers. This indicates that the website has been secured with an SSL certificate, which guarantees that the server you're communicating with is the server you intended to reach (authentication), and that only this server can read your information (encryption).

HTTPS has become the standard for any website that processes sensitive information, and is increasingly used for all websites to improve security, privacy, and performance.

HTTPS vs HTTP

The most significant difference between HTTP and HTTPS lies in the 'S' at the end of HTTPS, which stands for 'Secure'. While HTTP transfers data in plain text, which can be intercepted and read by anyone who catches the data while it's being transferred, HTTPS encrypts this data, making it unreadable to anyone except the intended recipient.

The encryption provided by HTTPS is particularly important for websites where sensitive information is transmitted, such as login credentials, personal information, or credit card details. Any website that requires users to log in should use HTTPS to ensure the security and privacy of its users.

HTTPS Encryption

HTTPS uses encryption to secure the connection between the client and the server. This encryption can be achieved using either SSL or TLS protocols, though TLS is more commonly used today due to its improved security.

In an HTTPS connection, when a client (browser) attempts to establish a connection with a server, they engage in what is known as an 'SSL handshake'. During this process:

1. The client sends a 'ClientHello' message to the server, including the SSL/TLS versions and cipher suites it supports.
2. The server responds with a 'ServerHello' message, selecting the highest SSL/TLS version and cipher suite they both support. The server also sends its digital certificate, which contains its public key.
3. The client verifies the server's certificate with a trusted Certificate Authority (CA). If verified, the client generates a symmetric session key using the server's public key and sends it back to the server.
4. The server decrypts the session key using its private key. Both the client and server now have the same session key, which is used to encrypt and decrypt the data they exchange.

Benefits of HTTPS

Using HTTPS brings several benefits:

• Data Security
  HTTPS encrypts the data between the client and server, protecting it from eavesdroppers and attackers.
• Authentication
  The certificate system used in HTTPS ensures that you're communicating with the server you intended to reach, preventing man-in-the-middle attacks.
• Trust and Credibility
  Seeing the https:// in the URL and the padlock icon in the browser gives users peace of mind that their information is secure, improving trust and credibility for the website.
• SEO Advantage
  Search engines like Google give a ranking boost to HTTPS websites, which can improve their search engine optimization (SEO).
• Requirement for Advanced Features
  Some advanced web features, such as geolocation and service workers, require websites to use HTTPS.