1. A multimode data processing apparatus adapted for receiving program statements in any of said modes and for branching to a particular mode based upon the composition of said statements, comprising: input means independent of a desired said mode for entering a program statement with a plurality of input characters including a plurality of alphanumeric characters which specify program lines in a higher order language and an alphanumeric character for specifying the end of the entry of input characters; an input buffer coupled to said input means for temporarily storing input commands and statements from said input means; an arithmetic logic unit operable in any of a plurality of data processing modes, including a program entry/edit mode responsive to said program statement for enabling selective entry and editing of program, said arithmetic logic unit coupled to said input buffer for executing data processing functions specified by said program statement stored in said input buffer in a selected data processing mode; an input mode interpreter, coupled to said input buffer and said arithmetic logic unit and activated after entry of said program statement alphanumeric character specifying the end of entry, for selecting one of said plurality of data processing modes in dependence upon the program statement characters stored in said input buffer; a read/write memory for temporarily storing data therein; said input mode interpreter selectively operable to select said program entry/edit mode for allowing a user to store program lines in said higher order language in said read/write memory and to edit said program lines if said input mode interpreter determines that the input characters stored in said input buffer comprise a program line by ascertaining that the input characters comprises an initial numeric integer followed by at least one space and an alphabetic character; and said arithmetic logic unit operable to store the input characters stored in said input buffer in said read/write memory in a location determined by said initial numeric integer when said program entry/edit mode is selected.