• Beginner level: When you are just starting, you want to make your first amigurumi and you don't know many stitches.
  
• Easy level: When you have been knitting for some time, you know different stitches, and you want to make an amigurumi that is not too complicated.
  
• Intermediate level: When knitting, sewing and knitting different stitches is no longer a challenge.
  

(These levels do not imply that if you are new to this world you can't make an “intermediate level” amigurumi, or that a beginner can't make an “easy level”. It's just an orientation, remembering how my beginnings were).