Microsoft has invested $1 billion in Sam Altman's OpenAI research lab, with the goal of developing artificial general intelligence inside its Azure platform. OpenAI will port their services to Azure, and Azure will be their preferred commercial partner, according to Microsoft's press release.

From OpenAI's blog post:

We’ll jointly develop new Azure AI supercomputing technologies, and Microsoft will become our exclusive cloud provider—so we’ll be working hard together to further extend Microsoft Azure’s capabilities in large-scale AI systems.

In an interview with the New York Times, Microsoft's CEO Satya Nadella said that much of the money will ultimately return to Microsoft:

Mr. Nadella said Microsoft would not necessarily invest that billion dollars all at once. It could be doled out over the course of a decade or more. Microsoft is investing dollars that will be fed back into its own business, as OpenAI purchases computing power from the software giant