GNU General Public License (GPL) means that the source code of all programs must be available for free, and that the whole program can be downloaded and used free of charge, even for commercial purposes. The programs are free, but the user has freedom to modify the source code and can redistribute the whole or parts of the program, but not with any sort of costs, exclusive terms or conditions, without even being asked to first contact the author or to get his permission.
A PDF file, Adobe Acrobat, is a Portable Document Format (PDF) file. The PDF file format is the standard file format for electronically archiving documents and it has become the de facto standard in the publishing industry for exchanging documents because it is robust, can be encrypted, has robust error trapping, and is suitable for viewing and printing. PDF files can also have images and can contain hyperlinks to other files, such as HTML or plain, text documents. This is one of the most popular file formats in the world, because it can be viewed and printed with many, but not all, browsers and printing devices. PDF files have three basic properties: the PDF file format is searchable and neutral; the information it contains can be archived, restored and combined with other information; and the information can be easily modified without affecting the rest of the original.
Photoshop (sometimes stylized as Photoshop) is a 2D and 3D graphics editor developed and marketed by Adobe Systems. It is designed for the digital creation, authoring, and management of high-quality graphics and for web, mobile device, gaming, and aerospace design. Photoshop is used for photo-manipulation (cropping, retouching, red-eye correction, dodging and burning, color correction, compositing, recoloring and recoloring). It can be used for simple graphics (adding text and web pages to images, creating 2D and 3D animations) or for more complex projects. Photoshop allows the creation of a range of digital designs, movies, video games, and mock-ups for web and mobile device apps. d2c66b5586