This paper describes the demo package for teaching and visualizing the Central limit theorem. The topic treated in this paper is of significant interest in undergraduate coverage of non-deterministic systems. Two types of random variables are considered: symmetric, highly concentrated about its mean value and nonsymmetrical random variables. The demo program is developed in MATLAB 5.2. The program gives the user step by step guidance. The user chooses the type of variable, the length of the sum N, and the corresponding parameters of a random variable. Successive plots of the sums of random variables and the estimations of the corresponding probability density functions are obtained. Finally the comparison with a normal variable is given.