This chapter contains sections titled: The C-value Paradox The Quantity of Transposable Elements Determines Genome Size General Classification Scheme for Transposable Elements Class II Elements Class I: The Non-LTR and LTR Retrotransposons Evolutionary Origins of Transposable Elements Non-autonomous Transposable Elements Transposable Element Demography and Genome Ecology Conclusions: Rehabilitation of Transposable Elements Acknowledgments References