This educational resource is a colourful and informative poster on the topic of “Perimeter” for GCSE students. It serves as a visual guide to understanding how to calculate the perimeter of various geometric shapes, including rectangles, squares, triangles, circles, regular polygons and compound shapes. Each section of the poster provides clear definitions, formulas and illustrated examples with step-by-step calculations. It explains the perimeter as the total length of all the sides of a shape and includes specific methods for different types of triangles, the formula for the circumference of a circle using diameter and radius, and tips for calculating the perimeter of complex compound shapes. This revision guide is an excellent tool for classroom walls and is suitable for students to reference during lessons or independent study to enhance their understanding of basic geometry principles.