HTTP stands for Hypertext Transfer Protocol. It is a protocol used for transmitting hypertext via the internet, making it possible for web pages to be linked and accessed. HTTP allows users to interact with web resources and servers by providing a standardized way for browsers to request and receive data. When you enter a web address starting with "http://", your browser uses this protocol to communicate with the server hosting the website, retrieving and displaying the content you requested. There’s also a secure version known as HTTPS, which includes encryption for enhanced security.