Java Problems

You need to tell the operating system where to look for the javac executable. If you're using Windows, this means setting the system 'path' environment variable to include the java 'bin' directory.

See the Java Tutorial, Path & Classpath (http://java.sun.com/docs/books/tutorial/essential/environment/paths.html).

Computers are good at following instructions, but not at reading your mind...
D. Knuth

Although it's good to know how things like javac and paths work, you'd be better off using an IDE (Integrated Development Environment - fancy name for a program that makes your programming easier) to do your Java programming. One that I like is NetBeans, you can get it here (http://www.netbeans.org/). It's got a lot of nice features to use. You can also try Eclipse if you're up for the challenge, although I always found it a little sluggish in comparison.

I disagree in this case. The OP obviously is just starting out with Java. I say use an IDE once you know Java, and use it for the conveniences it gives you, not because it lets you do something that you otherwise don't know how to do.

... Java is an annoying enough language as it is, its even worse to use the command line (like when you use javac you include the .java, but when you run the .class file you don't put the .class).I think you make Martin's case for him - if you'd started out learning how to use Java from the command line, the Javac and Java commands would be second nature - two commands really isn't much to learn, and you won't always have an IDE available - sometimes it's necessary to compile and run outside the IDE.
It's easier just to click "Run" in the IDE.True, once you've set it up. If you don't have the IDE you're familiar with for whatever reason, it's simple just to use the command prompt - if you know the basic Java commands.

The greatest obstacle to discovery is not ignorance, but the illusion of knowledge...
D. Boorstin