In this article, we review some of the complexities of jet algorithms and of
the resultant comparisons of data to theory. We review the extensive experience
with jet measurements at the Tevatron, the extrapolation of this acquired
wisdom to the LHC and the differences between the Tevatron and LHC
environments. We also describe a framework (SpartyJet) for the convenient
comparison of results using different jet algorithms.Comment: 68 pages, 54 figure