Close Call with a Dog on My Daily Commute: Why Do Dogs Suddenly Attack?

Today, I was driving to Calicut town and decided to take the shortcut to avoid traffic. As I was driving uphill, a dog suddenly jumped at me. I nearly fell over to the side, but I managed to control the handle of the bike, even though I was screaming. The only reason I came out of that situation unharmed was because I was able to maintain control. I could have fallen into a 50-foot downhill and possibly messed up my life because a dog just jumped at me. I didn't do anything to provoke it; I didn't make any sound with my bike and was driving at a normal speed. I still don't know why it decided to attack me. I often take that route daily and see dogs there, and they usually mind their business as I pass by. But today, Mr. Patty Sir took the game to the next level, and I could have lost my life. Does anyone know why dogs act like this suddenly? I remember stories of mad dogs attacking humans without provocation.