Drawing images in Java is very straightforward. To draw an image, you use one of the drawImage() methods defined in the Graphics class. Following is the simplest of the drawImage() methods:
The first three parameters to drawImage() specify the Image object to be drawn, along with its XY position. The image is drawn with its upper left corner at this position.
The last parameter, observer, is a special object used to keep track of the image as it is being loaded.