What does it mean? Very widely-used picture file format that saves storage space by throwing  away bits of the image and smoothing over the gaps.

Stands for Joint Photographic Experts’ Group

Picture file format that compresses files by smoothing out transitions and throwing away fine detail. When opening a JPEG file, it is good practice to save a working copy in another format for editing, because every time you save a file in JPEG format, yet more image detail will be deleted from the file.

The level of compression can be adjusted when exporting a final, compressed JPEG file. It is a versatile format used extensively in publishing and online. Sample applications include sending compressed, high resolution images by email, low resolution pictures on websites and many budget digital cameras save images in JPEG (.jpg) format to save storage space.

Good to know:

  • Supports RGB and CMYK colour spaces
  • Does not support transparency (rubbish for cutouts)
  • Compression degrades the image (“lossy compression.”) every time the file is saved or exported

What is it? Good quality image file format designed primarily for the internet.

Stands for: Portable Network Graphic

PNG (pronounced “ping”) is a reliable image file format for use online. It manages compression automatically, without throwing away image detail. PNG also supports transparency, which makes it an obvious choice for cutouts on websites. The PNG was developed as a replacement for the much older GIF format, which can also be used for cutouts and even animations, but has technical limitations that reflect its origins.

  • Supports RGB but not CMYK
  • Good for cutouts

 

What does it mean? Basic picture file format for printed work.

Stands for: Tagged Image File Format

Lowest common denominator picture file format: .tif files can be compressed without losing image detail (“lossless compression”). This is achieved applying data compression algorithms to the file contents – image editing software manages this operation automatically when opening or saving the file.

Beware!
PCs and Macs write and read .tif files in opposite directions: in practice a Mac will open and read a .tif file regardless of whether it was originated on a PC or a Mac (and can save for either platform); while a PC may refuse to open a Mac formatted .tif file unless it is running an industrial-weight image editor, like Adobe Photoshop

Good to know:

  • Supports RGB and CMYK colour spaces
  • Supports lossless file compression
  • Does not support transparency (rubbish for cutouts)