Translation is the communication of the meaning of a source-language text by means of an equivalent target-language text. The English language draws a terminological distinction (not all languages do) between translating (a written text) and interpreting (oral or sign-language communication between users of different languages); under this distinction, translation can begin only after the appearance of writing within a language community.
Sediments and landforms left behind by retreating glaciers can provide valuable information on the processes that shaped them. Reconstructing the behaviour of glaciers and ice sheets could provide important indicators of environmental change.