• each item has an identifying key (typically, a string)
• primary operations are: insert, search (by key)

SymTab insert(SymTab t, Item it) { ... }
Item *search(SymTab t, Key k) { ... }

Applications of symbol tables:

• programming language processors (e.g. compilers, interpreters)
• text processing systems (spell-checkers, document retrieval)
• implementing Set ADTs (insert = S ∪ {n},   search = n ∈ S)