Karlsruhe Accurate Arithmetic
Karlsruhe Accurate Arithmetic (KAA), or Karlsruhe Accurate Arithmetic Approach (KAAA), augments conventional floating-point arithmetic with good error behaviour with new operations to calculate scalar products with a single rounding error. The foundations for KAA were developed at the University of Karlsruhe starting in the late 1960s.
Source: Wikipedia — Karlsruhe Accurate Arithmetic (CC BY-SA 4.0)