What is format?

Format is the kind of file your picture downloads as. It doesn't change what the picture looks like on the screen; it changes how the file is stored, how big it is, and which apps can open it.

Your choices

• PNG: the best quality, with nothing lost when it's saved. Bigger files. The default for most tools, and the best choice for printing and editing.
• JPEG (also written JPG): smaller files that open everywhere, with a tiny loss of quality you'll rarely notice. The default for Motivational Pics posters. Good for sharing and email.
• WebP: a newer format with the smallest files at high quality, made for websites. A few older apps can't open it.

Which one should I choose?

If you're not sure, keep PNG. Pick JPEG to share or email a smaller file, or WebP to put the picture on a website.

The format you pick is also used for the larger 4K file if you choose one. 8K and 16K files are always a JPEG, to keep them a manageable size.

Related: What is aspect ratio? and What is resolution?