In evaluating evidence there are basically two types of proof . One is direct evidence, such as eye witness testimony or photographs. Another type of evidence is circumstantial evidence- that is evidence that leads to a conclusion based on a chain of facts and circumstances that point to the existence of a particular conclusion. For instance, if an eye witness saw a motor vehicle come to a quick, sudden stop and heard the screech of the tires on the roadway, he could testify to that and that would be direct evidence. The skid marks on the roadway alone would be circumstantial evidence that the vehicle that came to a stop, did so suddenly, and with a skid.