The TCP/IP protocol describes the “packets” transmitted across the internet. On top of that is required a protocol that understands the HTML that is requested and returned across the Web. “The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information systems. HTTP has been in use by the World-Wide Web global information initiative since 1990.”
In recent years companies have discovered that one reason it is hard to bring the data from disparate systems together is that they use terms differently. They were developed from different projects with priority being to get the particular system working, and little concern for how it interacted with other systems.