What is transientMap in node js and getTransient in chaincode

Question

What is the use of transientMap in channel.sendTransactionProposal(request, timeout) and getTransient() in chaincode?

Answer 1

TransientMap:

TransientMap  contains data that might be used to implement some form of application-level confidentiality. The data here in some cryptographic material.. This data is excluded from the ledger.. 

getTransient:

If you want to pass some data which you do not want to be kept in endorsement proposal you can use GetTransient API.