An HRIS is the database behind the HR function. Every employee has a record in it, and other people systems, from payroll to performance, either live inside it or draw from it. It is also called a Human Resources Information System, HRMS or HCM; the differences are mostly vendor marketing.
What sits in the core
Employee master data, organisation structure and headcount, onboarding and offboarding workflows, leave and attendance, documents, an ESS portal, and integrations with payroll and finance.
The global complication
One HRIS across countries is the goal and the main source of friction. Local payroll runs on different systems, statutory fields differ, and data held centrally falls under cross-border data transfer and data residency rules. Payroll integration is usually the hardest part.
How EOR Systems Affect Your HR Data
Employees hired through an Employer of Record exist on the EOR's system, not the client's. To see the whole workforce in one place, you either integrate the EOR platform with your HRIS or keep records twice. Ask which integrations a provider supports natively. If the answer is CSV exports, expect manual work every pay cycle.