https://youtu.be/3Hk0SzMtk38

A NaN value is used to represent the result of certain invalid operations such as dividing zero by zero. NaN constants of both float and double type are predefined as Float.NaN and Double.NaN.Floating-point operations. The Java programming language provides a number of operators that act on floating-point values.The comparison operators, which result in a value of type boolean: The numerical comparison operators, The numerical equality operators.(Early-plugs insertion point. A few seconds of silence in audiovisual.)The numerical operators, which result in a value of type float or double: The unary plus and minus operators, The multiplicative operators, The additive operators, the prefix and postfix increment operators, the prefix and postfix decrement operators.The conditional operator.The cast operator , which can convert from an floating-point value to a value of any specified numeric type.The string concatenation operator, which, when given a String operand and a floating-point operand, will convert the floating-point operand to a String representing its value in decimal form (without information loss), and then produce a newly created String by concatenating the two strings.Other useful constructors, methods, and constants are predefined in the classes Float, Double, and Math.If at least one of the operands to a binary operator is of floating-point type, then the operation is a floating-point operation, even if the other operand is integral.Any value of a floating-point type may be cast to or from any numeric type. There are no casts between floating-point types and the type boolean.The boolean type and boolean values. The boolean type represents a logical quantity with two possible values, indicated by the literals true and false.The boolean operators are: The relational operators, The logical complement operator, The logical operators, The conditional-and and conditional-or operators, The conditional operator, The string concatenation operator.The string concatenation operator, when given a String operand and a boolean operand, will convert the boolean operand to a String (either "true" or "false"), and then produce a newly created String that is the concatenation of the two strings.Boolean expressions determine the control flow in several kinds of statements: The if statement, The while statement, The do statement, The for statement.A boolean expression also determines which subexpression is evaluated in the conditional ? : operator.