It really depends on where you are and what type of snake.
Around here most of our snakes are Garter Snakes and Gopher (Bull) snakes. Both harmless. If I find a live gopher snake on the road, I'll try to shoo it away, just in case the next vehicle coming down the road isn't as snake friendly.
There are some rattlers (which look somewhat like the gopher snakes), but they're pretty rare now.
We don't have python weather here. Although the snake is an invasive species in Florida.