What is the point of using set and get in C Sharp?

It seems variables are used differently in this language than in C++.

For some reason, you have to have a static variable defined like this:

public static uint Somenum
{
   set { m_somenum = value; }
   get { return m_somenum; }
}

and prior to this declaration, you need to have this:

public uint m_sumenum;

This seems to be the only way to expose a member of a class to other classes in C#.

The problem is that I seem to be doing this improperly because I get a compile error:

An object reference is required for the non-static field, metod, or property '.......m_somenum"

1. Using get/set allow you to change the behavior of getting and setting later. If you have a field, you can't make something happen when it is assigned or accessed.  For example,

 public static uint Somenum
{
   set { m_somenum = value; CallOnChangeEventForSomenum(value); }
   get { return m_somenum; }
}

public static void CallOnChangeEventForSomenum(uint newValue)
{
  // do something whenever Somenum is assigned
}

2. To get the equivalent field, you need static in the declaration

public static uint m_sumenum;