The reason of Gharar disavow and its effect on transactions

The Gharar disavow issue in transactions has wide aspects on the juridical subjects and we can say that Gharar disavow is one of the traits of legal transactions in Islam; because many of human statutes apparently have supported some Gharar transactions such as bet and Gambling and in this age they use transactions with less Gharar. What makes review and study of Gharar important is that these transactions have so many shady cases, because in every manner of study we find it so rare in the transactions which have been accepted by Islam, so we should separate these cases.Yet we have some transactions which have been called "Gharari" by human statutes and some of them have acceded to Islamic jurisprudence and many of jurisprudents have accepted them and some have cautious view to them. In this article we will review Gharar and its aspects: 1. Custom description of Gharar 2. Idiomatic and juridical definition of Gharar (if any definition exists) 3. Considering of acceptable and unacceptable levels of it 4. Attention to effects of it on the collection of known transactions and indeed attention to the reasons of prohibition of Gharar in some of the transactions such as fruit selling before appears on the tree 5. Attention to effects of it on the new transactions such as insurance and lottery.