Cisco Prime Infrastructure as the name suggests is mainly for the network infrastructure components such as Data Center, WAN Managment, Cisco ISE etc whereas Cisco Prime Collaboration is mainly for the Collaboration (Unified Communication) products such as CUCM, UCCX/UCCE, Unity Connection, Telepresence etc.
Please go through the below Data Sheets to know more about both these products:
Data Sheet for Cisco Prime Infrastructure
http://www.cisco.com/c/en/us/products/cloud-systems-management/prime-infrastructure/index.html
Data Sheet for Cisco Prime Collaboration
http://www.cisco.com/c/en/us/products/cloud-systems-management/prime-collaboration/index.html
Regards
Deepak