PDF

PDF:

         Portable Document Format (PDF) was developed to allow a document to be ported from one location to another, without losing its appearance, layout and contents. Since this document is read only, its contents cannot be changed. Documents in this format can be created using Adobe Acrobat, and read using Adobe Acrobat Reader that's free to download and use. Third party tools such as pdf995 also allow you to create and read PDF documents.PDF documents can embed fonts and hence be read on any computer without losing their original appearance. The text and images in a PDF document can be copied easily. It can also embed buttons to trigger forms, sounds, and video. PDF standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991.PDF files may contain a variety of content besides flat text and graphics including logical structuring elements, interactive elements such as annotations and form-fields, layers, rich media (including video content), three-dimensional objects using U3D or PRC, and various other data formats. The PDF specification also provides for encryption and digital signatures, file attachments,and metadata to enable workflows requiring these features.