 All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.Many lakes are artificial and are constructed for industrial or agricultural use, for hydro-electric power generation or domestic water supply, or for aesthetic, recreational purposes, or other activities.The word "lake" comes from Middle English "lake" ("lake, pond, waterway"), from Old English "lacu" ("pond, pool, stream"), from Proto-Germanic *"lakō" ("pond, ditch, slow moving stream"), from the Proto-Indo-European root *"leǵ-" ("to leak, drain").