There are many different methods of scanning. The appropriate scanning solution would be chosen based on the original artwork size, shape, the desired resolution, and color. Here are a few different scanner types:

Small Flatbed scanners:
Scans original artworks or photographs. Some models come with a transparency adapter to scan slides or negatives up to 5" x 4".

Professional Large Format Flatbed scanners:
Same as a small flatbed scanner, but can scan larger sizes and are capable of much higher scanning resolutions.

Film Scanners:
For scanning film or transparencies only.

Drum Scanners:
Capable of extremely high quality results. Highly skilled operation. Not suitable for original artwork, only film.

Digital Cameras:
The image is captured into a digital file with no intermediate processing stage in-between. The image can be downloaded straight into the computer.

Digital Camera Backs:
Same as digital cameras, but produces a professional quality digital capture. A digital back that fits onto large format cameras, scanning directly into a computer interface.