Process methodologies (Waterfall, PRINCE2, Agile/SCRUM) and the broader management activities (initiation, screening, project manager role) used to deliver software predictably.
Key facts
Waterfall: plan-driven, sequential — best when requirements are stable.
Agile / SCRUM: adaptive, iterative — best when requirements churn.
PRINCE2: heavily documented, stage-gated, common in EU/government.