propose a situation where friction is desirable?

Question

ujjwal · Answer

As long as an object is at rest, it has static friction. The static friction increases with the increase in force applied. so, by increasing or decreasing the force applied, you can get a desirable frequency.

anonymous · Answer

friction would be desirable for example: walking, driving, braking....

ujjwal · Answer

In my above answer i meant "friction" at last

mani_jha · Answer

You can walk because of friction. Tyres can roll on the road because of friction. Do you know why? Try to think while walking, how you walk. You push the ground beneath you backwards. During this pushing, friction helps your feet stay firm on the ground, otherwise when you push backwards, your feet would move backwards more than desirable, and you would fall(That's what happens when you walk on ice or wet ground).

unklerhaukus · Answer

rock climbing

anonymous · Answer

Making love . . .    :">

anonymous · Answer

LOL

ujjwal · Answer

so basically the question is "How is friction useful?" 
well, i interpreted it in a different way. However, its answer is already given by kryten and mani_jha