Excavators at the Indus Valley site of Harappa in eastern Pakistan say the discovery of inscribed shards dating to circa 2800-2600 B.C. indicate their development of a Harappan writing system, the use of inscribed seals impressed into clay for marking ownership, and the standardization of weights for trade or taxation occurred many decades, if not centuries, earlier than was previously believed.

• Aindicate their development of a Harappan writing system, the use of  
• Bindicate that the development of a Harappan writing system, using  
• Cindicates that their development of a Harappan writing system, using  
• Dindicates the development of a Harappan writing system, their use of  
• Eindicates that the development of a Harappan writing system, the use of