Java Programming for Beginners
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Printing a string

Our goal with this HelloWorld program is pretty modest. When it runs, we'd like it to print some text to this output box at the bottom of our screen.

When we downloaded the Java SDK, we acquired a library of useful functions, one of which will do just this. This is the println(), or print line, function. When our Java code executes over this function, which it will do right away because it's the first function in our main() method's entry point, the Java code will print some words to our output box. Function names are followed by open and close parentheses. Inside these parentheses, we put information that the functions need to complete their task. The println() method, of course, needs to know what we would like it to print. In Java, a line of text is contained by two double quotation marks and we call it a string. Let's have our program print "Hello World!":