What Are The Differences Between Trusted & Untrusted Applets?

Both of these are used in the Java system.
The untrusted applet, don't have that much rights. These applets are just for showing a message box or other information boxes, these applets are not able to initiate any other program. It means that the untrusted applets that are uploaded on the internet are not permitted to access any file from the user system, and these applets are also not eligible for the establishment of any new connection with the network apart from the host, that is initiating the applet.
Moreover these untrusted applets are also not eligible for the initiation of any other program on the user system. These are also not permitted to initiate or run the libraries. And also not permitted to describe the local calls of the methods that are giving access to the original system.
On the contrary trusted applets have much more rights then the upper untrusted applets. All the facilities described above that are not given to the untrusted applets; these are available for the trusted applets. The trusted applets enable us to perform some functions. So in the trusted applets you can initiate the network connection from every place from which you desire, but never ever give the permission of accessing the files of the local systems.