More detail on class

// A class with a public variable and public method
class Computer
{   
    // variables
    public string brand;
    // No constructor, use default constructor
    // methods
    public string Start()
    {
        string str = brand + " Started";
        return str;
    }
    // Overload method
    public string Start(string mode)
    {
        string str = brand + " Started in " + mode + " Mode";
        return str;
    }

}
class Program
{
    static void Main(string[])
    {   
        Computer ibmComputer = new Computer;
        ibmComputer.brand = "IBM";

        Console.WriteLine(ibmComputer.Start("Safe"));

        Console.ReadKey();
    }
}