Hypertext Transfer Protocol. A protocol is a language used by computers to communicate with one another. HTTP is the internet's fundamental language to transfer hypertext documents on networks around the world.
URL
Uniform Resource Locator. URL are assigned to IP addresses to provide easy to remember addresses. The first part of the URL is the type of protocol (usually HTTP), then the domain name, and lastly the subdirectories. For example: http://www.hostinsight.com/indepth-review/hostmonster