- iCloud integration, for easy set up of your Mail, Contacts, Calendar, Messages, Reminders and Notes, and keeping everything, including iWork documents, up to date across all your devices

- the all new Messages app, which replaces iChat and brings iMessage to the Mac, so you can send messages to anyone with an iPhone, iPad, iPod touch or another Mac

- Notification Center, which streamlines the presentation of notifications and provides easy access to alerts from Mail, Calendar, Messages, Reminders, system updates and third party apps

- system-wide Sharing, to make it easy to share links, photos, videos and other files quickly without having to switch to another app, and you just need to sign in once to use third-party services like Facebook, Twitter, Flickr and Vimeo

- Facebook integration, so you can post photos, links and comments with locations right from your apps, automatically add your Facebook friends to your Contacts, and even update your Facebook status from within Notification Center

- Dictation, which allows you to dictate text anywhere you can type, whether you’re using an app from Apple or a third party developer

- AirPlay Mirroring, an easy way to wirelessly send an up-to-1080p secure stream of what’s on your Mac to an HDTV using Apple TV, or send audio to a receiver or speakers that use AirPlay

- Game Center, which brings the popular social gaming network from iOS to the Mac so you can enjoy live, multiplayer games with friends whether they’re on a Mac, iPhone, iPad or iPod touch.