JPEG is the most common image file format in the world. It is named after the Joint Photographic Experts Group, the committee that developed it in the early 1990s. JPEG uses lossy compression, which means it discards some data to make the file smaller. The compression is adjustable. A high-quality JPEG retains most of the detail. A low-quality JPEG discards more, producing visible artifacts, especially around edges and in areas of fine detail. The trade-off is file size versus image quality.

JPEG is a delivery format. It is what you share, upload, and print from. It is not an editing format. Every time you open, edit, and save a JPEG, you lose a little more data. That is why photographers shoot RAW and convert to JPEG only at the end. JPEG is also a standard. It is supported by every camera, every phone, every browser, and every photo app. That universality is its greatest strength. It is not the best format for every purpose. But it is the format that works everywhere.

JPEG facts

• Compression. Lossy, adjustable quality.
• Size. Small files, easy to share.
• Compatibility. Universal support.
• Editing. Not ideal for repeated edits.

JPEG is not the same as JPG. The two are the same format. JPG is a shortened extension used by older versions of Windows.