Language, Culture, Religion, Trade
It is impossible to decipher. It has 400 symbols that make up the language some of the symbols were single words and others make up other sentences.
Their people prospered and this is proved by them having children toys because it proves that they can make nonessential things in their society. Animals were a big part in the Harappans society. They had multiple drawings on paintings , toys, pottery, etc.
The leaders had close ties to those of religious importance. They had no temples and the priests prayed for food and safety. Religious artifacts like to the modern day religion Hinduism.
Gold came from the north from Afghanistan. Semiprecious stones Persia and the Deccan Plateau were crafted into jewelry. The indus river provided an excellent route for trading. Brightly colored cotton was a very valuable trade item since few people knew how to grow it.