Apple has unveiled its first update to the MacBook Pro laptop since 2012, which includes a secondary display between the keyboard and screen.

Launched earlier today, the new MacBook Pro features the Touch Bar – a strip of glass built into the top of the keyboard.

"We're introducing a new way to interact with your notebook," said Apple's chief design officer Jonathan Ive. "A multi-touch bar that provides a more intuitive, more immediate connection to your content."

This bar replaces the function keys and changes automatically based on what the user needs. It can be used to adjust volume and brightness, write with predictive text and emojis, skip through audio and video, and access shortcuts.

Icons on the bar will also be customisable in some apps.

"Commands that were once hidden are now visible, accessible and also customisable," said Ive. "In each application, the most relevant controls are displayed dynamically, allowing you to work with greater efficiency."

Additionally, the bar incorporates Touch ID fingerprint recognition technology, so users can unlock their machines almost instantly, as well as use Apple Pay on their laptops.

Integrated speakers have also been redesigned to provide up to 58 per cent more volume, and bass that is two and a half times louder.

Pressure-sensitive Force Touch trackpads are up to twice as large, providing more space for gestures during activities like digital drawing.

The main screen features brighter LED backlighting and an increased contrast ratio. Apple also claims that the models are up to 17 per cent thinner than the current devices.

"With our new design, the product's overall volume has been reduced dramatically," said Ive. "This results in an extremely purposeful and powerful creative tool."

The announcement coincides with the 25th anniversary of the release of the company's first notebook, the PowerBook, and follows a series of launches last month.

The iPhone 7 smartphone, AirPod wireless earphones and Apple Watch Series 2 were all revealed at the company's Keynote event in September 2016.