Cuneiform is the name given to the writing system invented by the Ancient Sumerians. This lettering emerged from pictographs and other logos used on clay slabs to describe trade items and animals. Over time, several languages were written in cuneiform including Sumerian, Akkadian, Elamite, and Babylonian. The original pictograph elements were eventually replaced with phonetic signs that represented sounds rather than objects (such as birds or animals). For example, a picture of a duck would be used instead of the actual word "duck" because it was assumed that nobody would know how to pronounce it. Around 2000 B.C., a syllabic script was developed where each sign also represented a syllable of a language. In addition to words, phrases, and sentences, the ancients also used cuneiform to record numbers. Although modern scholars believe that the Sumerians had no concept of zero, they did use different marks for many numbers up to about 10,000. After this, they simply wrote larger numbers in multiple rows of signs. Cuneiform remained popular until about 500 A.D., when it was replaced by Aramaic in the Middle East and Chinese characters in China. However, it is still used today in parts of Africa and Asia.