Progression is movement forward through a series of stages or steps, where each one builds on what came before. Think of learning to play piano: you start with simple scales, progress to easy songs, then tackle harder pieces. Each stage prepares you for the next one.

In mathematics, a progression is a sequence of numbers that follows a pattern. An arithmetic progression adds the same amount each time (2, 4, 6, 8), while a geometric progression multiplies by the same amount each time (2, 4, 8, 16). These patterns appear everywhere, from music to architecture to computer programming.

The word captures the idea that growth happens in steps, not all at once. A disease shows progression when it moves through predictable stages. A story has progression when events build toward a climax. Video games use progression systems where players unlock new levels and abilities as they advance.

When something is progressing, it's moving forward or developing. Your skills in drawing might progress from stick figures to realistic portraits. Notice that progression implies direction and purpose: it means moving toward a goal or through meaningful stages. It's the difference between wandering in circles and actually getting somewhere.