With InDesign you can determine the layout of flyers, brochures, posters, business cards, stickers, books, (roll-up) banners, magazines, newspapers and presentations. Everything you can print. You can easily export this layout to high resolution print files in PDF format that you can deliver to a printer.
With Illustrator you make illustrations, as the name suggests. But with Illustrator you can also make technical drawings, for example, cross-sections of machines. It is mainly used in the graphic world for designing a logo, typography and the design of graphic products, for example, pages of a brochure, a poster or a website.
With Photoshop you can recolor photos in an instant, retouch your old photos, ‘Photoshop’ your funny pictures together, create your online banners, create your own animated GIFs, draw a beautiful drawing or create a template for your social media.