General Motors, one of the world's largest car manufacturers, and Lyft, one of the world's biggest ride-hailing companies, are teaming up to develop driverless cars. It's a significant partnership, one that could fundamentally change the way we get around, and could help lift the fortunes of two companies that often operate in the shadows of their larger competitors.

GM and Lyft announced the joint venture on Monday, which also includes a $500 million investment by GM in Lyft. The San Francisco-based ride-hailing company, once known for the fuzzy pink mustaches affixed to the front of its vehicles, has also just completed a $1 billion round of financing, bringing its post-money value up to $5.5 billion. While this is a huge sum of money, it is still a fraction of Uber's eye-popping $62.5 billion value.

"There's a huge amount of change in the world of mobility."

In a brief phone interview Sunday night, GM president Dan Ammann said the investment was meant to send the signal that his company and Lyft were now in it for the long-haul.

"There's a huge amount of change in the world of mobility, especially in the urban environment," he said. "This investment is important, but more important is the long-term strategic alliance [between GM and Lyft]."

The announcement that the two companies will be working together, not only on driverless cars, but on driverless cars that will operate as for-hire vehicles, puts GM and Lyft on a level playing field with Uber, which is developing its own autonomous technology, as well as Google and Ford, which reportedly will announce a similar partnership during CES.

Still, it's still a unique partnership in many respects. So far, Uber is working by itself on its autonomous program, having poached a number of leading researchers from Carnegie Mellon University. Ford and Google's team-up is not necessarily strictly in the service of creating a fleet of for-hire vehicles, though it will likely include some on-demand aspect. GM and Lyft are billing their partnership as one that will help make an "integrated network of on-demand autonomous vehicles part of people's daily lives," the two companies said in a statement.

GM, which owns the OnStar in-vehicle communication service, has hinted for months that it was aggressively pursuing autonomous vehicle technology and was aiming to have a fleet of self-driving Chevy Volts roaming its Detroit campus by 2016. And GM and Ford are both experimenting with new modes of car use in the hopes of being a part of their own disruption.

"This is unique."

But driverless vehicles are still years away from being street-ready. In the short term, GM and Lyft will work together on a series of national rental hubs where Lyft drivers can rent short-term vehicles, unlocking new ways for people to earn money without having to own a car. John Zimmer, president of Lyft, said this would help bring more drivers onto Lyft's platform.

"This is unique," Zimmer said. "It's the only time a transportation network company, or ride-sharing company, has partnered with a leading auto manufacturer." Ammann added, "We have a common view of the future and what the future should look like."