it affects it greatly. For racing, the best tyres to use are called "slicks". This means that there is no tread on the tyre. The more tyre you have, the more grip you have. Road cars, however, need to have tread because the tread helps to grip in gravel and water. The tyre for normal road use is also designed so that it can get rid of the water that gets caught in the tread. As well, inflation of the tyre affects the surface area if under-inflated; the tread area collapses, even if you don't see much change with the naked eye. It makes a "mushy" less effective grip. If over-inflated, the tread has more pressure exerted on it from within, which widens the tread and lessens the grip on road surfaces.
Increases grip if there is water on the roadway the water can enter the holes in the tread and not interfere as much with the rubber contact with the road.
um... the tread
The "tread" is the part of the tire that is supposed to touch the ground. A tire with no tread would be a tire that is not supposed to touch the ground. You may be wondering why tires have a pattern of grooves (a.k.a., voids) in the tread. They're for bad weather. The grooves allow rain, and (if they're wider) mud and snow to squelch out from under the tire so that the tread can come into contact with something solid on which to get a grip.
to help clean the tread out allowing the tire to maintain as much grip as possible
Friction or grip if it's friction i think the tyre with the most contact with the road surface. If it's grip then the one with the tread
The grip? Perhaps the tread.
It is an indicator of tire tread wear.
If you mean tire tread depth, the minimum is 1.6mm.
Wider gives the machine more stability and load carrying ability
A tire reduces friction by creating a smooth interface between the road surface and the tire, allowing the tire to roll smoothly with minimal resistance. The design of the tire, including the tread pattern and material composition, helps to optimize traction and grip while minimizing friction.
To grip the road surface. You need tread especially in wet conditions.
Tire noise can be caused by the tread pattern used on your tires. Off road tires have a deep tread pattern to give better grip on soft surfaces. Change to a road tire. Road noise can also be caused by worn suspension components, especially the rubber bushes. Check that yours are not worn. They go soggy or split with age.