The notion of pictograph comes from the Latin word pictus. The term refers to a type of ideographic writing: that is, it resorts to symbols or conventional images for the idea representation, without fixed words that take care of its meaning.
In the specific case of pictography, objects are drawn and then explained using words. This writing arose in the Neolithic, when the prehistoric human being began to represent elements through drawings on stones.
In the pictograph, each of the signs carries a sentence or a sentence. Pictograms are figurative icons that seek to represent, in a real and schematic way, the objects in question.
According to the specialists, the pictography had a causative purpose, since with it the man I was looking to cause something. Thus, when a hunting scene was drawn, it was intended that this representation effectively had the effect of capturing prey.
As it is not associated with the phonetics or linguistic characteristics of a language, the pictography contributed to the communication. However, the impossibility of expressing abstract questions limited its development.
It is important to note that the pictograph continues to be used today. Many instructions and signs in public spaces are presented with pictograms for ease of understanding. The He drew of a locomotive, to mention a case, can indicate the proximity of a railway station or a level crossing: this indication is reflected through the pictograph.
Anyway, it is almost impossible to find universal symbols. That is why cultural differences restrict the scope of the pictograph.