What is a pdf? And other file formats...
Portable Document Format was invented by Adobe Systems. When you convert documents, forms, graphics, and web pages to PDF, they look just like they would if printed. But unlike printed documents, PDF files can contain clickable links and buttons, form fields, video, and audio.
PDF’s are used in graphic design to send brochures, logos etc to the printer. They are also a simple way to show clients what the finished design will look like because anyone can ‘read’ the files whether they are on Macs or PC’s using free Adobe Reader® software.
JPEG stands for Joint Photographic Experts Group, the committee that created the file type. They are the most common file type for images taken with digital cameras, and generally used for photos and other graphics on websites. When JPG files are saved, they use “lossy” compression, meaning that each time you open a jpeg file and then re-save it, it loses some definition. Jpegs can be used in print but because they use ‘lossy compression’ they do not lend themselves to being manipulated and updated constantly.
If you are sending images to a designer send the biggest file size you can. (Pixelated images are one of the main headaches a designer has!) Images from the web are generally unusable because of the small file size, and asides from that there can be copyright issues.
The Portable Network Graphics format. PNG is similar to a JPEG in that it is used for images and graphics on the web. The unique thing about PNG is that it can be saved with a transparent background for putting logos and other shapes onto pages that have coloured backgrounds.