Meta Data: Meta Data is the information about Data. It gives the information about structure of data or MetaObjects.
Master Data: This Data is key business information like Customer information ,Vendor information, Employee , Materials etc. This is more like a reference data. For Ex. If a customer orders 10 units of your product instead of asking customer for his shipping address 10 times , the same can be referenced from the Customer Master Data.
Transaction Data: This is data related to day to day transactions.