Question

How did pictograph differ from an ideograph

Answer 1

Pictographs resemble what they mean. For example, a pictograph of "Tiger" would be more or less recognizable as the image of a tiger crudely drawn. 
Ideographs do not resemble what they mean. However, Ideographs can resemble one another (i.e. the ideograph of "Tiger" may resemble the ideograph of "Lion", but neither would resemble a Tiger or Lion crudely drawn). Ideographs can also steal phonetic pieces (i.e. The ideograph for "Shipping" may have the ideograph for "ping" in it since "ping" is phonetically part of "Shipping"). Finally Ideographs can be composed of multiple minor ideographs working in concert (i.e. "Archer" may be written as combination of "bow" and "man" since the Archer is man who uses a bow). None of the combination-elements are present in pictographs.