Besides portability, another of Java's key advantages is its set of security features which protect a PC running a Java program not only from problems caused by erroneous code but also from malicious programs (such as viruses). You can safely run a Java applet downloaded from the Internet, because Java's security features prevent these types of applets from accessing a PC's hard drive or network connections. An applet is typically a small Java program that is embedded within an HTML page.
