Nearly three-quarters of a trillion dollars. That’s how much Apple Inc. (NASDAQ: AAPL), the world’s current most-valuable, and most-profitable company is worth at recent stock prices. Over the past nearly 20 years, Apple has disrupted and come to dominate multiple industries, changing the way people listen to — and buy — music, use computers, and interact with technology in their everyday lives. It’s not a stretch to say that Apple, if not invented, then perfected, the mobile computing era.