MacBook
The MacBook is a brand of Macintosh notebook computers designed and marketed by Apple Inc. that use Apple's macOS operating system since 2006. It replaced the PowerBook and iBook brands during the Mac transition to Intel processors, announced in 2005. The current lineup consists of the MacBook Air (2008–present) and the MacBook Pro (2006–present). Two different lines simply named "MacBook" existed from 2006 to 2012 and 2015 to 2019. Overview. The MacBook family was initially housed in designs similar to the iBook and PowerBook lines which preceded them, now making use of a unibody aluminum construction  first introduced with the MacBook Air. This new construction also has a black plastic keyboard that was first used on the MacBook Air, which itself was inspired by the sunken keyboard of the original polycarbonate MacBooks. The now standardized keyboard brings congruity to the MacBook line, with black keys on a metallic aluminum body. The lids of the MacBook family are held closed by a magnet with no mechanical latch, a design element first introduced with the polycarbonate MacBook. The Memory, drives, and batteries were accessible in the old MacBook lineup, though the newest compact lineup solders or glues all  such components in place. All of the current MacBooks feature backlit keyboards. The MacBook was discontinued from February 2012 until March 2015, when a new model featuring an ultraportable design and an all-metal enclosure was introduced. It was again discontinued in July of 2019 following a price reduction of the 3rd generation MacBook Air and discontinuation of the 2nd generation model. MacBook family models. Current. MacBook Air. The MacBook Air is Apple's least expensive notebook computer. While the 1st generation was released as a premium ultraportable positioned above the 2006 - 2012 MacBook, lowered prices on subsequent iterations and  the discontinuation of that MacBook has made it serve as the entry-level Macintosh portable. The 2010 to 2017 base model came with a 13-inch screen and was Apple's thinnest notebook computer until the introduction of the MacBook in March 2015. This MacBook Air model features two USB Type-A 3.0 ports and a Thunderbolt 2 port, as well as an SDXC card slot (only on the 13inch model). This model of MacBook Air did not have a Retina Display. A MacBook Air model with an 11-inch screen was available from October 2010 to October 2016. In  2017, the MacBook Air received a small refresh, with the processor speed increased to 1.8 GHz. On October 30, 2018, the MacBook Air underwent a major design change, dropping the USB Type-A ports, MagSafe, and the SD card slot in favor of two USB-C/Thunderbolt 3 ports and a headphone jack. It was updated with a Retina display and Intel Y-series Amber Lake i5 CPUs, as well as a Force Touch trackpad, a third-generation butterfly mechanism keyboard, and the Touch ID sensor found in the fourth-generation MacBook Pro, but without the Touch Bar. The base  price was also raised, although the base configuration of the 2017 model was retained until July 9, 2019, when it was discontinued along with the Retina MacBook. The base price of this model was also dropped to $1099 ($999 for students) on the same day. On November 10, 2020, Apple announced that the MacBook Air would use the new Apple M1 system on a chip. The new Air does not have a fan, ensuring silent operation, but limiting the M1 chip speed in sustained operations. Performance was claimed to be higher than most current Intel laptops. MacBook Pro . The MacBook Pro is Apple's higher-end notebook available in both 13-inch and 16-inch configurations. The current generation 13-inch MacBook Pro was introduced in October 2018. It features a touch-sensitive OLED display strip located in place of the function keys, a Touch ID sensor integrated with the power button, and four USB-C ports that also serve as Thunderbolt 3 ports. The 13-inch model was also available in a less expensive configuration with conventional function keys and only two USB-C/Thunderbolt 3 ports, but since July 2019, the base MacBook Pro model has  the Touch Bar as well as quad-core processors, similar to the higher-end models, although it still has only two USB-C / Thunderbolt 3 ports. The May 4, 2020 refresh adopts many of the upgrades seen in the 16" 2019 MacBook Pro, including the scissor mechanism keyboard ("Magic Keyboard") and a physical Escape button. On November 13, 2019, Apple released the 16-inch MacBook Pro, replacing the 15-inch model of the previous generation, and replacing the butterfly keyboard with a scissor mechanism keyboard (dubbed the Magic Keyboard by Apple), reverting to the old "inverted-T" arrow key layout , replacing the virtual Escape key on the Touch Bar with a physical key, and replacing the AMD Polaris and Vega graphics from the 15-inch model with options from AMD's Navi graphics architecture, as well as reengineering the speakers, microphone array, and the thermal system compared to the 15-inch; the latter had thermal limitations in the 15-inch model due to its design. In addition, the 16-inch is available with up to 64 GB of DDR4 2667 MHz RAM and up to 8 TB of SSD storage. It also has a 100 Wh battery; this is the  largest battery that can be easily carried onto a commercial airliner under U.S. Transportation Security Administration rules. On November 10, 2020, Apple announced a new model of the MacBook Pro incorporating the new Apple M1 system on a chip. Apple will continue to sell versions of the MacBook Pro with Intel processors. The MacBook Pro with M1 SoC incorporates a fan, allowing sustained operation of the M1 chip at its full performance level, which is claimed to match or exceed that of Intel versions. Unlike Intel Pro models, the M1 version only comes with a 13-inch screen, has only  two Thunderbolt ports and has a maximum of 16 GB random access memory (RAM). On October 18, 2021, Apple announced updated 14-inch and 16-inch MacBook Pro models during an online event. They are based on the M1 Pro and M1 Max, Apple's first professional-focused ARM-based systems on a chip. This release addressed many criticisms of the previous generation by reintroducing hard function keys in place of the Touch Bar, an HDMI 2.0 port, a SDXC reader and MagSafe charging. Other additions include a Liquid Retina XDR display with thinner bezels and an iPhone-like notch , ProMotion supporting 120Hz variable refresh rate, a 1080p webcam, Wi-Fi 6, 3 Thunderbolt 4 ports, a six-speaker sound system supporting Dolby Atmos, and support for a third 6K display on M1 Max models. The 16-inch version is bundled with a 140W GaN power supply that supports USB-C Power Delivery 3.1, though only MagSafe supports full-speed charging as the machine's USB-C ports are limited to 100W. Discontinued. The original MacBook was discontinued on July 20, 2011, for consumer purchase and in February 2012 for institutions, being superseded by the 2nd generation MacBook Air , as the 11-inch model introduced in 2010 had the same starting price of the MacBook. The sales of the Mac computers amounted to 18.21 million units in Apple’s 2018 fiscal year. The Retina MacBook was a line of Macintosh portable computers introduced in March 2015. It was discontinued on July 9, 2019, as it had been superseded by the 13-inch Retina MacBook Air, which had a lower base price, additional USB-C / Thunderbolt 3 ports, and better performance. All Intel-based MacBook Air and MacBook Pro models were discontinued in November 2020 and October 2021 respectively, and  replaced by Apple silicon models.