Cop 2510 midterm study guide print method: system. out. print( hi ); String concatenation: used to attach some info to user input, the operator is + . It can also be used to append a number to a string, + is also used for arithmetic addition. If both operands are strings, or if one is a string and one is a number, it performs string concatenation. If both operands are numeric, it adds them. System. out. println( 24 and 45 concatenated: + 24 + 45); System. out. println( 24 and 45 added: + (24 + 45)); A program is made up of one or more classes. A class contains one or more methods. A method contains program statements: each statement is followed by a semicolon. A java application always contains a method called main: where to start an application. The name of the file always matches the name of the class. The words a programmer uses in a program: identifiers.