<P> The unibody - construction MacBook Pro largely follows the styling of the original aluminum iMac and the MacBook Air and is slightly thinner than its predecessor, albeit wider and deeper due to the widescreen display . The screen is high - gloss, covered by an edge - to - edge reflective glass finish, while an anti-glare matte option is available in the 15 - and 17 - inch models in which the glass panel is removed . The entire trackpad is usable and acts as a clickable button . The trackpad is also larger than the first generation model's, giving more room for scrolling and multi-touch gestures . When the line was updated in April 2010, inertial scrolling was added, making the scrolling experience much like that of the iPhone and iPad . The keys, still backlit, are now that of Apple's now - standard sunken keyboard with separated black keys . </P> <P> During the MacWorld Expo keynote on January 6, 2009, Phil Schiller announced a 17 - inch MacBook Pro with unibody construction . This version diverged from its 15 - inch sibling with an anti-glare "matte" screen option (with the glossy finish standard) and a non user - removable lithium polymer battery . Instead of traditional round cells inside the casing, the lithium - ion polymer batteries are shaped and fitted into each laptop to maximally utilize space . Adaptive charging, which uses a chip to optimize the charge flow to reduce wear and tear, extends the battery's overall life . Battery life for the 17" version is quoted at eight hours, with 80 percent of this charge remaining after 1,000 charge - discharge cycles . </P> <P> At Apple's Worldwide Developers Conference (WWDC) on June 8, 2009, it was announced that the 13 - inch unibody MacBook would be upgraded and re-branded as a MacBook Pro, leaving only the white polycarbonate MacBook in the MacBook line . It was also announced that the entire MacBook Pro line would use the non user - removable battery first introduced in the 17 - inch MacBook Pro . The updated MacBook Pro 13 - and the 15 - inch would each have up to a claimed seven hours of battery life, while the 17 - inch would keep its eight - hour capacity . Some sources even reported up to eight hours of battery life for the 13 - and 15 - inch MacBook Pros during casual use, while others reported around six hours . Like the 17 - inch MacBook Pro, Apple claims that they will last around 1,000 charge cycles while still containing 80 percent of their capacity . Graphics card options stayed the same from the previous release, although the 13 - inch and the base model 15 - inch, came with only the GeForce 9400M GPU . The screens were also improved, gaining a claimed 60 percent greater color gamut . All of these mid 2009 models also included a FireWire 800 port and all except the 17 - inch models would receive an SD card slot . The 17 - inch model would retain its ExpressCard / 34 slot . For the 13 - inch MacBook Pro, the Kensington lock slot was moved to the right side of the chassis . In August 2009, Apple extended the "matte" anti-glare display option to the 15 - inch MacBook Pro . </P> <P> On April 13, 2010, Intel Core i5 and Core i7 CPUs were introduced in the 15 - and 17 - inch models, while the 13 - inch retained the Core 2 Duo with a speed increase . The power brick was redesigned and a high - resolution display (of 1,680 × 1,050) was announced as an option for the 15 - inch models . The 13 - inch gained an integrated Nvidia GeForce 320M graphics processing unit (GPU) with 256 MB of shared memory, while the 15 - and 17 - inch models were upgraded to the GeForce GT 330M, with either 256 or 512 MB of dedicated memory . The 15 - and 17 - inch models also have an integrated Intel GPU that is built into the Core i5 and i7 processors . The 15 - inch model also gained 0.1 pounds (0.045 kg). Save for a third USB 2.0 slot, all the ports on the 17 - inch MacBook Pro are the same in type and number as on the 15 - inch version . All models come with 4 GB of system memory that is upgradeable to 8 GB . Battery life was also extended further in this update, to an estimated ten hours for the 13 - inch and 8--9 hours on the 15 - and 17 - inch MacBook Pros . This was achieved through both greater power efficiency and adding more battery capacity . One reviewer reported about six hours of battery life through a continuous video battery stress test in the 15 - inch and another, who called the battery life "unbeatable", reported nearer to eight in the 13 - inch through their "highly demanding battery drain test". </P>

What are the different sizes of macbook pro