This is a public domain calculator for Microsoft Windows that is modeled after the Hewlett-Packard HP-16c.  It uses Reverse Polish Notation, which uses the ENTER key instead of the "=" (equals) key.

In addition to all the functions you'd expect from an ordinary calculator, the application also has many features specifically designed for the computer professional: Floating point, Decimal, Hexadecimal, Octal and Binary modes.

This is written by Emmet P. Gray  
HQ, III Corps & Fort Hood
Attn: AFZF-PW-ENV
Directorate of Public Works
Environmental Division
Fort Hood, TX 76544

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