OpenMP

I got introduced to this in my second CUDA course.

https://www.openmp.org/resources/

I found this when looking at Multithreading for Eigen https://eigen.tuxfamily.org/dox/TopicMultiThreading.html

OpenMP is an application programming interface that supports multi-platform shared-memory multiprocessing programming in C, C++, and Fortran, on many platforms, instruction-set architectures and operating systems, including Solaris, AIX, FreeBSD, HP-UX, Linux, macOS, and Windows. Wikipedia