2 megapixels

• A 2-megapixel camera will take pictures that are 1200-pixels-by-1600-pixels. Those pictures can typically only print in sizes up to 4-inches-by-5-inches. Many phone cameras have a 2-megapixel resolution.
  
  

6 megapixels

• 6-megapixel cameras take photos that are 2400-pixels-by-3000-pixels in size. Photos taken with these cameras can typically be printed out in sizes up to 6.5-inches-by-10-inches. Many moderatly priced consumer cameras have a resolution around 6-megapixels.
  
  

10 megapixes

• A 10-megapixel camera takes pictrures at a resolution of 2592-pixels-by-2872-pixels. The cameras can print pictures up to 8.5-inches-by-13-inches with a clear resolution. 10-megapixels is a high resolution for a consumer camera, and is the resolution of several professional models.
  
  

12 Megapixels

• 12-megapixel cameras take pictures at a resolution of 4200-pixels-by-2800-pixels. Pictures taken with the cameras print out in sizes up to 16-inches-by-24-inches with a clear resolution.