Abstract: A character-serial electronic digital computer utilizing a four character vocabulary, each character being represented by two binary bits, is structured to process character-serial data arriving at the computer in a manner specified and initiated by the arriving data. Data structures that may represent program or operations to be performed on data arriving at the computer input are stored in the computer's storage area in the form of nested data structures that may be illustrated as tree structures in which each node of the tree structure represents an operation. Data structures that may represent operands are also supplied to the computer in a nested organization. This operand data addresses a certain node or operation resident in the computer storage area. The linking up of the arriving operand data with its program data triggers execution of the operation.