Name varies depending on the camera, but basically I mean the mode where the camera enables ALL of its focus points across the frame to select a subject to focus on. Why would you want that? I don't want to play focus roulette with where my camera is going to decide something looks like it's worth focusing on. I use center spot, or zone focusing groups a lot. Zone is a particular favorite because I have flexibility about where to place my frame around the focus point, while still pointing the camera to my intended subject. But I see no value in arbitrary focusing across the entire frame. Especially because tiny adjustments in framing can lead the camera to pick totally different focus points. I just don't see the value in multi/wide AF setting, no matter what camera you're using.