In color theory, a purple is defined as any non-spectral color between violet and red (excluding violet and red themselves). The spectral colors violet and indigo are not purples according to color theory, but they are purples according to common English usage since they are between red and blue.
Apex Learning was started in 1997 by Microsoft co-founder Paul Allen on the idea that online courses and test prep, which were already succeeding in higher education, could be applied to K-12.
Although Lewis Terman later supplanted Goddard as the authoritative voice on intelligence testing, it was Goddard who created the intelligence testing industry. Thus, he's responsible for popularizing psychological science in America and providing psychology practitioners with their chief assessment tool.