JPG – a Digital Image Format

What is a JPG file?

A JPG (or extended JPEG, Joint Photographic Experts Group file) is an image file format. Some JPG image files use the .jpg file extension and others .jpeg, but it is important to emphasize that this is the same type of file. The extensions we can find to characterize this file type are: .jpg, .jpeg, .jpe, .jif, .jfif, and .jfi.

Nowadays, JPG is one of the most widespread "lossy compression" methods for digital images. The degree of compression can be adjusted giving you control over the image file size and its quality. JPG has the task to achieve the best possible compression with as little quality loss as possible. It typically achieves 10:1 compression that does not show much difference in quality other than file size. Note that JPG compression can reduce the quality of the image (it might be noticeable if the image is highly compressed).

JPGs are highly versatile and constitute the most common image format on the web. The biggest reason for this is the fact that JPG is the best choice for photos and images that you want to send via email, for images meant for storing, or posting on websites. Compressed images reduce the time of upload, and download, which generally improves the user experience. It is best used for photographs and realistic paintings, and not suitable for line or images with text or large blocks of colors. The so-called "crisp" lines create a blur effect, and the colors can change.

How to open a JPG file?

Since the JPG image format is well integrated and widely used, there is almost no photo editor that does not support it. You can open it with any browser or image viewer (online services, such as Google Drive included). If you are a Mac user, use Apple Preview and Apple Photos to open the JPG file.

Mobile devices also provide support for opening JPG files. You can easily view them in your email and through text messages without needing a specific JPG viewing app.

List of some programs that can open JPG documents:

  • Adobe Photoshop
  • Adobe Suite
  • Apple Preview
  • Corel Paint Shop Pro
  • Microsoft Office
  • Microsoft Windows Photo Gallery Viewer
  • Most web browsers
  • GIMP
  • IrfanView, etc.