why binding with list doesn't work?

Question

when i bind itemsource with a list ..it does't work..why?
like..datagrid.datacontext=MyList;

but when i keep that list inside a class..
Myclass
{
ObserableCollection MyList
}
Myclass myclass=new myclass();
datagrid.datacontext=myclass;

it works...

Answer 1

datacontext cannot bind myclass type

Answer 2

can u elaborate ?