UPDATED September 2022: They have a new webpage no longer directly on the Penguin Random House website (although they are still an imprint): https://astrapublishinghouse.com/imprints/daw-books/. They no longer appear to be open to direct submissions. I will update if that changes.
DAW is an imprint of Penguin that is open to manuscript submissions from authors without an agent. This is unusual and a great opportunity. DAW is a highly respected publisher of Science Fiction and Fantasy. DAW has published authors such as Marion Zimmer Bradley and Roger Zelazny. DAW has published many bestselling books and they have published Hugo award winning books. They are respected and very popular.
DAW novels vary in length, but they are rarely contain less than 80,000 words, so keep that in mind. They have a fairly long wait time for responses if the book makes it past the first reader. However, they have made some efforts to reduce that wait time in recent years.
Although they ask for exclusive submissions, if you have waited for longer than 3 months, your work can be submitted elsewhere. This is a recent improvement they made to their submission policy.
They have previously only accepted hard copy submissions but on December 31st, 2017, they transitioned to digital only submissions. They just reopened to submissions, now accepting only digital submissions through Submittable.
To learn more visit their website here.