1. Fluids differ from solids in that they cannot resist deformation and will flow under applied forces. Fluids are classified as Newtonian if shear stress is directly proportional to rate of shear strain. 2. The viscosity of a fluid represents its resistance to flow and is dependent on temperature. The boundary layer is a region near solid surfaces where viscous effects dominate due to the no-slip condition. 3. Bernoulli's equation relates pressure, velocity, and elevation for fluid flow. It states that for steady, incompressible flow, the sum of kinetic energy, potential energy, and pressure energy remains constant.