After years of mapping the world's streets with panoramic views, Google is now taking its efforts underwater.

On Wednesday, the internet giant unveiled the newest addition to its Google Maps service: 360-degree underwater images of some of the ocean's coral reefs.

Now users can swim with turtles in Australia's Great Barrier Reef, explore the ocean floor near the Philippine's Apo Island and follow a school of fish in Hawaii's Hanauma Bay — all without having to slip into a wetsuit.

The feature is an extension of Google Maps' street view application, which provides panoramic views along many streets around the world.

"We're trying to build the most accurate, comprehensive … user-friendly map out there," said Google spokesperson Aaron Brindle on Wednesday.

He said that attempting to chart the oceans, which cover 70 per cent of the planet, is the next ambitious step in that mandate.

State-of-the-art technology

Earlier this year, Google partnered with Catlin Seaview Survey, a scientific organization that studies living coral reefs around the world. The group is responsible for capturing thousands of underwater images.

Catlin worked with a Sydney-based organization called Underwater Earth to develop the state-of-the-art technology required for the project.

A proprietary camera called the SV2 is able to capture and store thousands of images as a scuba diver carries it through the water. These images are later stitched together to create the 360-degree views.

"This is not like going down there with a waterproof camera," said Brindle.

The tablet-controlled device can reach a depth of 30 metres and is capable of recording location data for each image through geo-tagging technology. It also contains image recognition software that is able to instantly assess the amount of coral cover and other life forms in locations along the entire length of the reefs.

Users can currently explore six underwater locations: Wilson Island, Heron Island and Lady Elliot Island along the Great Barrier Reef; Molokini Crater and Hanauma Bay in Hawaii; and Apo Island in the Philippines. Google hopes to include more locations in the future, particularly spots along the Great Barrier Reef, which spans about 2,600 kilometres.

While many are using the new tool as a fun way to explore the planet's watery depths, others have already realized its potential scientific value. An article on the New Scientist website says that a tiny Denise's pygmy seahorse was spotted in the images — the first time the species has been seen in Australian waters.

"As a consumer it is just so fun and there's a novelty there," said Brindle. "But this imagery is available to everyone whether you're just working at your desk or you're a scientist interested in marine biology."