What is the difference between an end-bearing pile and a friction pile?

1. An end-bearing pile develops most of its capacity at a hard stratum or rock at the tip; a friction pile develops capacity along the embedded shaft
2. A friction pile must always be made of timber; an end-bearing pile must be steel
3. End-bearing piles are used only in water; friction piles are used only on land
4. There is no difference; both terms mean a spread footing