Flavors of Exchange Server 2013

                                          

Standard Edition	Enterprise Edition
for small size organization	medium and large size organization
Supports 5 Databases	Supports 50 Databases
Storage limit 50 GB For 1 database limit is 50 GB 5 X 50=250 GB	No Storage limit (Microsoft  theoretical valve has given as 16 TB) But Microsoft has recommend to configure with 2 TB