  The sorting problem is one of the most relevant problems in computer science.
Within the scope of modern computer science it has been studied for more than
70 years. In spite of these facts, new sorting algorithms have been developed
in recent years. Among several types of sorting algorithms, some are quicker;
others are more economic in relation to space, whereas others insert a few
restrictions in relation to data input. This paper is aimed at explaining the
fusion tree data structure, which is responsible for the first sorting
algorithm with complexity time smaller than nlgn. The nlgn time complexity has
led to some confusion and generated the wrong belief in part of the community
of being the minimum possible for this type of problem.
