Apple said in March that the event would be online-only due to the coronavirus pandemic, but had not said when it would be hosted.
In 2019, Apple used the event to announce some hardware, including the Mac Pro. Apple may have already revealed most of its new gadgets for the first half of the year since a digital event would make it impossible for everyone to see and try the new products in person.
Apple announced the new iPads Pro and MacBook Air in March and its latest 13-inch MacBook Pro on Monday. The iPhone SE also launched last month. It's possible other Mac computers, including a refreshed iMac, are revealed during the event. Apple also hasn't updated the Apple TV since 2017.
WWDC usually starts off with a big keynote on the opening day and follows with several days of developer sessions where people can learn about new software capabilities.
The most exciting parts usually include hearing about new features coming to the iPhone, Mac, iPad, Apple TV and Apple Watch. That software doesn't typically launch until the fall after Apple announces new iPhones in September, however.
The Apple Developer app, which typically has a schedule of events, doesn't say much more than WWDC 2020 will start on June 22 and that further announcements will come in June.