• Through templates the programming languages, provide parametric polymorphisms,  facilitating type (data-type) safe (meaning by passing runtime errors;
• If not specialized for any data type, default is void type, meaning would accept any data-type.
• Allow generic algorithms and data structures, encapsulated in a class.
• Template works like a run-time code optimizer, reduces run time over head and memory foot prints.

• C# 2.0
  List<Person> foo = new List<Person>();
  • C# does not allow non-type template parameters, such as template C<int i> {}.
  • C# generics do not provide the same amount of flexibility as C++ templates.
  • Further readings ref: 2
• Java
  • simple
    List<String> list12 = new ArrayList<>();
    List<Person1> foo1 = new ArrayList<Person1>();
    List<Person1> foo2 = new ArrayList<>();
  • Observable:
    ObservableList<String> oString1 = FXCollections.<String>observableArrayList(ext1.list1);
• C++
  exmple1 ,

References:

1. http://stackoverflow.com/questions/31693/what-are-the-differences-between-generics-in-c-sharp-and-java-and-templates-i?noredirect=1&lq=1
2. https://msdn.microsoft.com/en-us/library/c6cyy67b.aspx