what is Singleton class? [Resolved]

In whole single web application I have used 3 asp.net pages.
Shall I say that I have used Singleton class here in my application..is Class1 here is singleton???
if no what is Singleton class?


page1.aspx.cs

public class1{
function1(int a){}

}


page2.aspx.cs
public class2{
class1 c =new class1();
c.function1(1);
}

page3.aspx.cs
public class3{
class1 c =new class1();
c.function1(2);
}

[Resolved]