Twitter - A small group of employees from Odeo, the San Francisco podcasting startup where Twitter initially began, had a brainstorming session. They were trying to come up with names that fit with the theme of a mobile phone buzzing in your pocket with an update. After narrowing down the options (which included Jitter and Twitter), they wrote them down, put them in a hat, and let fate decide. Fate decided on Twitter as the name was literally picked out of a hat.
Yahoo - Founders David Filo and Jerry Yang started what would become Yahoo when they were Ph.D. candidates at Stanford University. The project originally consisted of categorized lists of favorite links on the web, which made its original name, “Jerry and David’s Guide to the World Wide Web,” at least accurate if not so catchy. Yahoo is actually an acronym for “Yet Another Hierarchical Officious Oracle.” According to the company, the team chose the name for its definition: “rude, unsophisticated, uncouth.”