  The purpose of this paper is to present results and open problems related to
R-places. The first section recalls basic facts, the second introduces R-places
and their relationship with orderings and valuations. The third part involves
Real Algebraic Geometry and gives results proved using the space of R-places.
Theorem 14 gives explicitly, in terms of the function field of the variety, the
number of connected components of a non-empty smooth projective real variety.
The fourth and fifth parts are devoted to the links with the real holomorphy
rings and the valuation fans. Then we present an approach to abstract real
places and conclude with some open questions.
