Chapter $3,$ Project Management$,$ discusses the difference between the$$ waterfall$$ approach to controlling projects versus $$the agile$$ style of management. With the$$ first, waterfall,$$ well$-$defined projects have changes small enough to be managed without substantially revising plans. The projects progress smoothly in a$$ step$-$by$-$step manner through each phase. But many$$ projects, like software$$ development, are$$ ill$-$defined and need an agile approach with constant feedback and adjustments. Such projects are tackled$$ incrementally, and small chunks meet limited objectives.