Ebook: Trees

The present book is an English translation of "Arbres, Amalgames, SL(2)", published in 1977 by J-P.Serre, and written with the collaboration of H.Bass. The first chapter describes the "arboreal dictionary" between graphs of groups and group actions on trees. The second chapter gives applications to the Bruhat-Tits tree of SL(2) over a local field.