What's an enum class and why should I care?

Question

For one who has never written a line of C++11, and who has, at the moment, no opportunity to program in C++11, can you, in one short paragraph., tell me:

What is an

Answer 1

Personnally I have used it in a tcp based messaging protocol: many of the fields were enum values that I needed to encode inside one byte only, so as to respect the messaging interface..

All my enums were simply defined this way:

enum class EnumFieldA : unsigned char { eValProperty1, eValProperty2};
enum class EnumFieldB : unsigned char { eValProperty1, eValProperty2, eValProperty3};
enum class EnumFieldC : unsigned char { eValProperty1, eValProperty2, eValProperty3, eValProperty4};
...

there are also plenty of thorough answers in this SO question.