It is exceedingly difficult to classify.

It is not certainly evangelistic work, though it is commonly organised by evangelistic workers; it is not educational in the sense that educational missionaries accept it as a definitely recognised part of their work, though educational methods are employed and it often has a distinctly educational purpose.

It is sometimes a form of Sunday service almost akin to a Church service.

It is often a form of children's school where the religious teaching given, or neglected, during the week in the day school is supplemented: it is sometimes a form of elementary school for adults, Christian, or inquirers: it is a form of Bible school for adult Christian workers.

It is a method of propaganda for the conversion of heathen children or adults.