Click image on thumbnails page for information about the image and availability of high-resolution versions.
Web (seen on-screen)
The small (thumbnail) and medium-sized images seen on-screen have a resolution of 72 ppi, making them suitable for web page use when there is no text or fine detail. They are not suitable for printing. They can be used in PowerPoint presentations that WILL NOT be printed for handouts. Because of their small file size, they can be used temporarily in Word or PowerPoint documents that need to be circulated in emails during the writing, editing, or review phase of document preparation.
"Full-Size" or Medium Resolution
These images have a resolution of 150 ppi and are suitable for use in PowerPoint presentations, especially those that will be printed for handouts; for online publishing, particularly when the image contains text or fine detail; and for other informal desktop printing.
Press or Print Quality ("Hi Res")
These images have a resolution of 300 ppi and are for use in documents that will be printed on a printing press or other Postscript device or printer. High-resolution PDF files also are available upon request when portability is an issue.