Google Inc. surprised the tech world yesterday afternoon when it announced it was undergoing a massive reorganization, with the end product being a new holding company called Alphabet. Alphabet Inc. will be the name of the new conglomerate, with Google, YouTube, Android mobile software, and other properties (think Google Maps) being key components.

To make sure you didn't miss any of the finer details from yesterday, here are seven things you need to know about Google's becoming Alphabet:

1. Alphabet's goal with the new hierarchy is to provide deeper insight into how it will invest in various ventures that are not related to its core search and advertising business, such as driverless cars, high-speed internet services, and health-related technologies.

2. Larry Page, Google's co-founder and CEO, will be promoted to CEO of Alphabet Inc., while Google co-founder Sergey Brin will be Alphabet's president.

3. Sundar Pichai, long considered Larry Page's second in command at Google, will now serve as Google Inc.'s CEO.

4. Rumors have it that part of the motivation for this reorganization and Sundar Pichai's promotion to Google Inc. CEO was that Twitter had offered him its CEO role.

5. Wall Street was in favor of the new changes. Shares of Google rose to $680 in extended trading, up nearly 5.5 percent on the day.

6. Outside of Google, there are six main subdivisions of the newly formed Alphabet Inc.: Calico, the research company known for its life sciences work to extend human lifespans; Nest, the $3.2 billion acquisition Google made in 2014 for its smart thermostat; Fiber, Google's high-speed broadband business; Google Ventures and Google Capital, the venture arm; and finally Google X, the secret lab where Google experiments with things like self-driving cars.

7. There's a hidden joke inside Google's letter announcing Alphabet. Inspired by the HBO hit TV series Silicon Valley, Alphabet's letter includes an inside joke referencing "XYZ." Fans of the TV series will remember that this was Hooli's (the Google knockoff in the show) biggest failure.