Laminar/Turbulent Flow
A laminar boundary layer is one where the flow takes place in parallel layers. In simple terms the flow is smooth, allowing for better performance. If you consider an aircraft wing, the boundary layer at first will flow smoothly over the streamlined shape of the aerofoil. Here the flow is laminar and there is a laminar boundary layer.
On the other hand a turbulent boundary layer is when the flow takes place by mixing of several layers and the flow is chaotic. As the flow develops along the surface, the boundary layer becomes thicker and unstable. This leads to the flow and boundary layer becoming turbulent.
On the other hand a turbulent boundary layer is when the flow takes place by mixing of several layers and the flow is chaotic. As the flow develops along the surface, the boundary layer becomes thicker and unstable. This leads to the flow and boundary layer becoming turbulent.