What is the difference between addresses that start with "R" and addresses that start with "z"?

Komodo Platform is built upon and extends the Bitcoin protocol. It also uses zero knowledge technology. 

Addresses which start with "R" behave exactly like Bitcoin's, including their globally public properties and we refer to these as "transparent addresses". 

Addresses which start with "z" include the privacy enhancements provided by zero-knowledge proofs (pioneered by Zcash) and we refer to these as "shielded addresses". It is possible to send KMD between these two address types.