Chinese pictogram characters are an essential part of Chinese characters.
Over time, Chinese characters are developed based on several strategies. Some Chinese characters, including commonly used ones, were originally pictograms. They symbolize objects or express meanings iconically. Pictogram Chinese characters are easy to recognize as the objects represented in the symbols can be seen as soon as the meaning is revealed.
Here is a good video made by Shanghai Animation Film which shows the evolvement of 36 commonly used Chinese pictogram characters：