Silver the periodic table) is useful in nuclear reactors because of its high thermal neutron capture cross-section, good conduction of heat, mechanical stability, and resistance to corrosion in hot water. The word "silver" appears in Anglo-Saxon in various spellings, such as "seolfor" and "siolfor". A similar form is seen throughout the Germanic languages (compare Old High German "silabar" and "silbir"). The chemical symbol Ag is from the Latin word for "silver", "argentum" (compare Ancient Greek ἄργυρος, "árgyros"), from the Proto-Indo-European root *"h₂erǵ-" (formerly reconstructed as "*arǵ-"), meaning "white" or "shining": this was the usual Proto-Indo-European word for the metal, whose reflexes
Symbol table global scope, whether it is imported, and what namespace it belongs to. Some programming languages allow the symbol table to be manipulated at run-time, so that symbols can be added at any time. Racket is an example of such a language. Both the LISP and the Scheme programming languages allow arbitrary, generic properties to be associated with each symbol. The Prolog programming language is essentially a symbol-table manipulation language; symbols are called "atoms", and the relationships between symbols can be reasoned over. Similarly, OpenCog provides a dynamic symbol table, called the "atomspace", which is used for knowledge representation. Symbol table