A STATIC block is automatically executed the first time the class where it is defined is called.

Difference between static block and static method:

static block will execute when ever execution starts, it means this block executes first of all, where as static block have to call separately and also it can call with out object instance.

Here is an example:

public class StaticTest {

static{
System.out.println("Hello from static block");
}
public static void helloMethod()
{
System.out.println("Hello from static method");
}
public static void main(String[] args) {
helloMethod();
}
}