Lets create a contract.contract Helloworld { string hello = “Hello World”; function sayHello() returns (string) { return hello; } } The code of contract goes between curly braces. The name HelloWorld is the name of our contract. It’s not necessary that the name has to be name given to the file. The keyword contract here can be treated similar to a class in C++/java. Where class has methods and variables so are here. Let’s see. The string variable is like a normal OOP string variable nothing f...