pdf: PDF stands for Portable Document Format. As the name implies, it is a data format that can be used to describe documents. Adobe, the developers of PDF, market software to create, edit and visualize PDF files. Because the specifications of the file format are publicly available and meanwhile even became an official ISO-standard, a lot of other companies develop PDF-related software as well. In prepress, PDF is commonly used as a format to exchange data, either complete pages that need to be printed or advertisements that needs to be included in a publication. The file format is also popular for softproofing and reviewing content, because there are applications that allow you to make annotations on the PDF pages.
Jpeg: JPEG compression is used in a number of image file formats. JPEG/Exif is the most common image format used by digital cameras and other photographic image capture devices; along withJPEG/JFIF, it is the most common format for storing and transmitting photographic images on the World Wide Web. Unlike GIF files, which show significant loss in photo image quality, JPGs allow for some degree of file size reduction without losing too much image quality. However, as file sizes get very low, JPG images will become “muddy.” When saving photos and other images as JPG files for the web, email and other uses, you must decide on this tradeoff between quality and file size.
tiff: TIFF (Tag Image File Format) Part of the Computing fundamentals glossary: TIFF (Tag Image File Format) is a common format for exchanging raster graphics (bitmap) images between application programs, including those used for scanner images. TIFF files can be in any of several classes, including gray scale, colour palette, or RGB full color, and can include files with JPEG, LZW, or CCITT Group 4 standard run-length image compression.
png: PNG (pronounced ping as in ping-pong; for Portable Network Graphics) is a file format for image compression that, in time, is expected to replace the Graphics Interchange Format (GIF) that is widely used on today’s Internet. PNG files were developed to build upon the purpose of gifs. Designers need the ability to incorporate low-resolution images that load quickly but also look great, too. This is where PNG comes in. PNG-8 does not support transparency, but PNG-24 and PNG-32 do. PNG transparency is different from Gif transparency, because they can have different levels of transparency. Gifs are either transparent or opaque. Below is a comparison of how a gif will look if the edges of the image are blurred or they are semi transparent.