In the following diploma thesis, we have compared Photoshop with three cost-effective raster image processing programs - Gimp, Photopea and Fotor. The purpose of the thesis was to compare alternatives regarding the product, procedures, speed of work, functionality of tools, updates of new versions and compromises in the use of each program compared to working with Photoshop. In the theoretical part, we first explored the history of raster graphics - the definition, its beginnings and the reason for its emergence and existence. We then listed and described the basic raster formats (JPG, PSD, TIFF, PNG, GIF, RAW) and described Photoshop and its versions. The comparison in the practical part includes features that are mostly expected from more powerful raster image editing programs, such as colour profile determination, working in the cloud, auto colour corrections, adjustments, HDR, lens distortion correction, red-eye correction, selections and work with layers, working with channels and masks, vectors, texture libraries, font and brush styles, geometric transformations, guides, animation and 3D. We introduced the workflow and presented the results for each of the functions. In the final part, we concluded that each program has its advantages as well as drawbacks, and the choice depends on the following factors: purpose of use, speed of work, price, set of features and their functionality, computer storage capacity, layout and clarity of the working environment and compatibility with operating systems. Photoshop is a fitting choice for professional users who do not mind the cost and want to work with a wide range of quality features. Gimp and Photopea are suitable alternatives for users who want to edit images with most of the professional features Photoshop provides (also for professional purposes), but free of charge. Fotor, with its free trial version, can be recommended for non-demanding users who want fast and easy editing of images with basic or some more advanced features that have certain limitations.