Though the PMBOK doesn't explain it, these would be your proprietary tools (i.e. Microsoft Project for #2) or a Web-based application within your corporation's Project Management Office for #1. #3 could be your human resource management tool that tracks how many hours your employees work so they are paid correctly. There isn't a one size fits all. If it helps you clarify further, think about #1 being a largest database of all the projects going on, #2 is the software to help you manage a single project, and #3 helps you with scheduling resources for use within a project.
The following user(s) said Thank You: Nizar Al-Odaini
Michael DeCicco, PMP
Moderators: Yolanda Mabutas, Ahmed Amin, Scott Gillard, Mary Kathrine Padua, ERIC BARTLETT, Gail Freedman, Kevin Nason, Steven Mudrinich, PMP, Mark Wuenscher, PMP, John Wolverton, Tracy Shagnea, PMP, Jada Garrett
This interview with Simona Fallavollita (LinkedIn Profile) was recorded at the magnificient Project Management Institute (PMI)® Global Conference 2017 in Chicago, Illinois. We discuss the how, what, why and when of the changes that are coming to the PMP exam.