The MacBook Pro is a line of Mac laptops made by Apple Inc. Introduced in January 2006, it is the higher-end lineup in the MacBook family, sitting above the consumer-focused MacBook Air. It is currently sold with 13-inch, 14-inch, and 16-inch screens, all using Apple silicon M-series chips. The original MacBook Pro used the design of the PowerBook G4, but replaced the PowerPC G4 chips with Intel Core processors, added a webcam, and introduced the MagSafe power connector. The 15-inch model was introduced in January 2006; the 17-inch model in April. Later revisions added Intel Core 2 Duo processors and LED-backlit displays. The unibody model debuted in October 2008 in 13- and 15-inch variants, with a 17-inch variant added in January 2009. Called the "unibody" model because its case was machined from a single piece of aluminum, it had a thinner flush display, a redesigned trackpad whose entire surface consisted of a single clickable button, and a redesigned keyboard. Updates brought Intel Core i5 and i7 processors and introduced Intel's Thunderbolt. The Retina MacBook Pro was released in 2012: the 15-inch in June, a 13-inch model in October. It is thinner than its predecessor, made solid-state storage (SSD) standard, added HDMI, and included a high-resolution Retina display. It eliminated Ethernet and FireWire ports and the optical drive. The Touch Bar MacBook Pro, released in October 2016, adopted USB-C for all data ports and power and included a shallower "butterfly"-mechanism keyboard. On all but the base model, the function keys were replaced with a touchscreen strip called the Touch Bar with a Touch ID sensor integrated into the power button. A November 2019 revision to the Touch Bar MacBook Pro introduced the Magic Keyboard, which uses a scissor-switch mechanism. The initial 16-inch model with a screen set in narrower bezels was followed by a 13-inch model in May 2020. This revision also modified the Touch Bar, as users were complaining about the ESC key disappearing and not being able to exit a computer window. Therefore, now it is put as a whole button as it was standard before Touch Bar Macs. Another revision to the Touch Bar MacBook Pro was released in November 2020; it was the first MacBook Pro to feature an Apple-designed system on a chip, the Apple M1. The 14-inch and 16-inch MacBook Pros were released in October 2021. Powered by either M1 Pro or M1 Max chips,