Export Settings
The configurations used to save or output a file at a specific format, size, or quality.
In practice
Export settings decide what a working file becomes when it leaves the design tool: file type, pixel size, resolution, color mode, compression and whether transparency is kept. The same artwork needs different settings for different uses. A poster might be exported as a print PDF with bleed and CMYK color, while its web version becomes a compressed RGB JPEG 1600 pixels wide, small enough to load quickly on a phone.
Often confused with Format
Export settings include the file type, such as JPEG or PDF; format, in this dictionary, means the size and proportions of the designed object, such as A4.
Try this
Export one image as a JPEG at three quality levels, compare the file sizes, and find where the loss becomes visible.