• variables(name,type, value, scope, and lifetime)
  e.g. Graphics g
• parameters and arguments
  public abstract void drawString(String str,int x,int y)
g.drawString("Welcome to JAVA", 30, 30);
public void drawRect(int x,int y,int width,int height)
g.drawRect(20, 5, 140, 50);

java.lang.Object
  |
  +--java.awt.Component
        |
        +--java.awt.Container
              |
              +--java.awt.Panel
                    |
                    +--java.applet.Applet