Hamsters Need Love
There are 5 domesticated species of hamsters
Chinese
Syrian
Roborovski Dwarf
Winter White Dwarf
Campbell's Dwarf
Hamsters are often mistreated because they are thought of as 'easy pets' as they are a small animals and aren't as easy to unuderstand as bigger animals such as dogs and cats.
"Animals, no matter how small, are hard to care for — they are a constant responsibility that cannot be pushed aside or ignored, and the moment someone buys an animal they need to be ready to commit not only to keeping it alive, but to helping it live the most healthy and fulfilling life that it can.

Animals are not entertainment and they are not a way for people to teach their kids responsibility. They are living beings with needs and wants and lives, no matter how small or simplistic they might be. Just because we own them doesn’t mean that we have the right to let them die."
Common ways Hamsters are mistreated
Putting them in a small cage with no/ little toys or hideouts
Putting them in groups
Feeding them unsafe food or too much food
Bathing them in water
Using bedding that is toxic to them
Getting a wheel that is too small for their size