Fewer is often confused with "less".
Use fewer with things you can count ("digital").
- I have fewer shoes in my closet now that I've cleaned it out and donated 4 pairs of shoes to charity.
- Jane has fewer books than Tim.
- Zoe has fewer money than Dale.
- Corrected: Zoe has less money than Dale. or Zoe has fewer dollars than Dale.
- "Fewer vs. Less" by Philip B. Corbett, in a New York Times blog.