Apple's Mail app will also gain some new features, many of which are reminiscent of the iPhone and iPad versions of the app. For example, new gestures include swiping to delete an email, just like in iOS. You can also swipe right to mark as unread.
There's also an option to hide windows within the app without minimizing them - just click on the inbox to minimize the message you are composing to the bottom of the screen, a bar will indicate its presence. You can click on that bar to open the email again, but you may not need to: you can drag attachments into this minimized window to include them in the email you are composing.
Mail also gains better integration with calendar and contacts - this means that if you receive an email from someone who isn't in your contacts Mail will offer to add them. If a friend invites you to meet up Mail will offer to create a calendar event for you.
Other new features include tabbed windows to manage different email threads and natural-language search so you can search for "emails from Ashleigh including photographs" for example.
Data detectors mean Mail will offer to add events to your calendar and contacts to your address book. This isn't a new feature, but it is improved in El Capitan Mail. It will adds banners in between the address field and the body of the message with data Mail's detected and possible actions you might like to take.
IMAP support is also set to improve in Mail 9, thanks to a new engine that makes it twice as fast, according to Apple. Mail will change the say it downloads messages, prioritising the ones in the inbox you are viewing, so you shouldn't have to wait for Mail to synchronize your messages before you can read any of them.
Apple Metal updates
There is one more significant change coming to OS X El Capitan, Metal, the graphics technology that was announced with iOS 8. Metal will bring improved game performance and improved performance in processor hungry apps.
Metal is a core graphics technology that gives apps near-direct access to the GPU. According to Apple, Metal will make graphics rendering 40 percent more efficient and games drawing performance is 10 times faster. Apple also claims better battery life because of a 40 percent reduction in the CPU require to do graphics.
Metal combines OpenCL and OpenGL into a single API, bypassing the OpenGL framework. OpenGL runs slowly on OS X, dragging professional Mac apps down in comparison to their Windows counterparts, so bypassing OpenGL and making apps run natively on top of Metal is good news.
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