title: How do inline variables work?
body: <p>At the 2016 Oulu ISO C++ Standards meeting, a proposal called <a href="http://open-std.org/JTC1/SC22/WG21/docs/papers/2016/p0386r0.pdf" rel="noreferrer">Inline Variables</a> was voted into C++17 by the standards committee.</p>
  
  <p>In layman's terms, what are inline variables, how do they work and what are they useful for? How should inline variables be declared, defined and used?</p>