The original correspondence courses were carried out through the postal service.
Who would return essays and projects for grading.
A correspondence courses is an academic Class that is taken.
Most correspondence corses today take place over the internet,but the concept is same :students anywhere can take classes without having to physically be present at the school.
The by-mail model was slow but generally effective ,particularly for very busy students.professors almost always set deadlines,but students were free to organize their own day-to-day schedules.so long as the materials were postmarked by the appointed date,how or when the work got done was not really an issue.
Correspondance courses are named for their postal origins. As early as the 1800s,students enrolled in university distance learning programs would mail their school work to professors much the same way would have mailed business or personal correspondence.the instructor would grade the material then send on the next assignment.