If you are confused about the topic, read this article:

Type Deduction and Braced Initializers

by Arne Mertz

From the article:

I just finished watching a talk from CppCon 2014 by Scott Meyers: Type Deduction and Why You Care. All in all it was a very interesting and entertaining talk, and I learned a thing or two, especially about the combination of type deduction and braced initializers. Since this blog is about simplifying the use of C++, I want to have a short look at that special combination and derive a rule of thumb from it...