In addition to gravity applied globally to dynamics, you can also add other forces. A force is any influence that causes a dynamic item to undergo a change in speed or direction. Forces are global in nature and can affect both dynamic items as well as particle items, simultaneously, if desired. There are seven different types of forces available to affect dynamic objects: linear, radial, drag, turbulence, vortex, wind and curve force. Each of them are covered in detail in the following sections.