An introduction to Java geometry expert. This paper gives a brief introduction to the system Java Geometry Expert (JGEX). This system consists of three parts: the drawing part, the proving and reasoning part, and the most distinctive part -- the part for generating visually dynamic presentation of proofs in plane geometry. The current version of JGEX is beta 0.80, which is available at our website woody: url{http://woody.cs.wichita.edu}.