"JPEG files achieve a smaller file size by compressing the image in a way that retains detail which matters most, while discarding details deemed to be less visually impactful."
"JPEG stands for "Joint Photographic Expert Group" and, as its name suggests, was specifically developed for storing photographic images
my understanding is that in a JPEG pixels that are similar get the same value. As far as whats better for printing it depends on the size of the print and what you want from that print, generally TIFF would be better for prints IMO.
jpeg & TIFF: Image Types: JPEG & TIFF File Formats
- Only save an image using a lossy compression(jpeg) once all other image editing has been completed, since many image manipulations can amplify compression artifacts.
- Avoid compressing a file multiple times, since compression artifacts may accumulate and progressively degrade the image.
RAW format: Tutorials – The RAW File Format
- One problem with the RAW file format is that it is not very standardized. Each camera has their own proprietary RAW file format, and so one program may not be able to read all formats.
- Adobe has announced a digital negative (DNG) specification which aims to standardize the RAW file format.