Boots with screw-in studs are the most popular.
They offer a player the opportunity to adjust their footwear depending on the conditions.
If the pitch is particularly muddy then it is a good idea to use a longer set of studs, changing to shorter studs on a drier day.
And an extra set of studs is cheaper to buy than another pair of boots.
When changing or tightening studs, it is a good idea to apply a bit of grease to the thread, to prevent rusting.