The key differences between Photoshop and Illustrator lie in their core functionalities and intended use cases. Photoshop is primarily a raster-based program, meaning it works with pixels, making it ideal for photo editing, digital painting, and detailed image manipulation. Illustrator, on the other hand, is vector-based, using mathematical paths to create scalable graphics, which makes it perfect for logos, icons, typography, and illustrations that need to maintain clarity at any size. Photoshop excels in handling complex textures, color grading, and photorealistic effects, while Illustrator is designed for clean, precise, and infinitely resizable designs. Additionally, Photoshop integrates well with raster-heavy workflows, whereas Illustrator is the go-to for creating graphics that require smooth scaling and precision. Both are complementary, often used together in professional design projects.