This is usually in Kilobytes or Mega Bytes (KB/MB). The file size is important as it affects the quality of image (sharpness), storage requirement (hard disk space) and the network delivery speed (file transportation). In general the larger the file size the higher the quality of the image, the greater the storage requirements and slower the network delivery speed possible.
It means how the image is structured. File formats relate to the type of computer coding that is used to structure a digital image.
Resolution is the number of pixels in a digital image. It is expressed as ‘ppi’ (pixel per inch) or ‘dpi’ (dots per inch). The higher the resolution the higher the quality of image and possible output size.
This is the amount of color information per pixel in an image. It is measured in factor of 8 i.e. 8bit, 16bit, 24bit etc.
The color space a digital image is in, relates to its achievable color out put. There are two prominent types:
RGB (Additive color process, using Red, Green and Blue)
CMYK (This is the color space used for print industry)