  This is neither an elementary introduction to singularity theory nor a
specialized treatise containing many new theorems. The purpose of this little
book is to invite the reader on a mathematical promenade. We pay a visit to
Hipparchus, Newton and Gauss, but also to many contemporary mathematicians. We
play with a bit of algebra, topology, geometry, complex analysis and computer
science. Hopefully, some motivated undergraduates and some more advanced
mathematicians will enjoy some of these panoramas.
