What is the difference between an int and an Integer in Java and C#?

Question

I was reading More Joel on Software when I came across Joel Spolsky saying something about a particular type of programmer knowing the difference between an i

Answer 1

have you ever programmed before then (int) is one of the primitive types you can set for your variables (just like char, float, ...).

but Integer is a wrapper class that you can use it to do some functions on an int variable (e.g convert it to string or vise versa,...) , but keep note that methods in the wrapper classes are static so you can use them anytime without creating an instance of Integer class. as a recap :

int x;
Integer y; 

x and y are both variables of type int but y is wrapped by an Integer class and has several methods that you use,but i case you need to call some functions of Integer wrapper class you can do it simply.

Integer.toString(x);

but be aware that both x and y are corect but if you want to use them just as a primitive type, use the simple form (used for defining x).