Microsoft has acquired Adobe Systems for $1.9 billion, marking the company’s largest acquisition to date.

The deal, which was announced Monday, also includes Adobe’s PCM software business.

The deal is expected to close in the second half of 2018, according to people familiar with the matter.

Microsoft said in a statement Monday that Adobe is committed to continuing to develop innovative products and services that enhance the PCM platform.

The acquisition “will further Microsoft’s efforts to create and enhance the software ecosystem that powers the PC and personal computing devices in every corner of the world.”

The purchase is a major win for Microsoft, which has struggled to bring its Windows-based operating system to the masses in recent years.

Adobe has focused on mobile devices and the iPad, with no success.

Microsoft has also struggled to build its own desktop operating system for its Surface tablets and laptops.