One of the most important areas of research in concurrent algorithms was in numerical linear algebra operations. Many (if not most) scientific problems that can be solved using a computer involve solving linear systems.
Two of the most important operations on vectors of data are the linear combination of two vectors (also called a SAXPY operation due to the name of the FORTRAN subroutine in the LINPACK library that performed this operation) and the inner (or dot) product of two vectors.