How did World War 1 begin and ultimately how did it end?

WW I began in 1914 with the assassination of Arch Duke Franz Ferdinand of the Austro-Hungarian Empire, by a Serbian separatist (Serbia used to be part of the Austro-Hungarian Empire) and ended in 1918 after a tremendously destructive war, as a result of the sheer exhaustion of the Central Powers. The formal end of the war was the signing of the Treaty of Versailles (which was, as it turned out, a very badly designed treaty which became a major cause of WW II).