Can someone please explain this diagram

Project Name Number Location Department Employee Dept Name Dept Number Employee Start Date Location 1 Location2 Location3 Location 4 Location5 EmployeeName Social Security Number SSN Address Salary Sex Date Of Birth DOB Department Project 1, Project 2, 3, 4,5,6, 7, etc Supervisor Hours Per Week on Project 1 Hours per Week on Project 2, 3, 4 Dependant First Name Date Of Birth DOB Relationship with dependant Location (Loc) Location Name Address co ordinates Loc Number