PDFCreator is an application for converting documents into Portable Document Format (PDF) format on Microsoft Windows operating systems. It works by creating a virtual printer that prints to PDF files, and thereby allows practically any application to create PDF files by choosing to print from within the application and then printing to the PDFCreator printer. In addition to PDFCreator Free, there are three business editions with additional features: PDFCreator Professional, PDFCreator Server and PDFCreator Terminal Server. Since 2009, PDFCreator has included closed source adware, toolbars and other software that is installed by default. Implementation The application is written in Microsoft C# and released to the public at no charge. It works with 64-bit and 32-bit Windows versions including Windows 11. The actual PDF generation is handled by Ghostscript, which is included in the setup packages. Besides being installed as a virtual printer, PDFCreator can be associated with .ps files to manually convert PostScript to PDF format. PDFCreator can convert to the following file formats: PDF (including PDF/A (PDF/A-1b, PDF/A-2b and PDF/A-3b) and PDF/X (X-3:2002, X-3:2003 and X-4)), PNG, JPEG, TIFF, TXT. It also allows to digitally sign PDF documents. PDFCreator allows any COM enabled application to make use of its functionality. The business editions of PDFCreator allow users to write their own C# scripts with access to the entire job data. These custom scripts can be integrated directly before and after the conversion. They have full access to the .NET-framework and can reference compatible external libraries. PDFCreator allows the user to disable printing, copying of text or images and modifying the original document. The user can also choose between two types of passwords, user and owner, to restrict PDF files in several ways. The former is required to open the PDF file, while the latter is necessary in order to change permissions and password. Encryption can be either Low (128 Bit), Medium (128 Bit AES) or High (256 Bit AES), with the latter only being available in the PDFCreator Business editions. PDFCreator provides the possibility for automating certain tasks, for example with the help of user tokens. These placeholders for values, like today’s date, username, or e-mail address can be helpful when printing many similar files like invoices. With PDFCreator users can verify their authorship of a document with digital signatures. This feature is part of all PDFCreator editions, including PDFCreator Free. Starting with version 0.9.6, there is full support