well I can tell you what they do:
Tamagotchis are a hand held virtual pet and originated from Japan. It's in the shape of an egg but there are manny different types of Tamagotchi there are 31 different types. Tamagotchis were very popular in the late 1990's. here are some things you can do with your Tamagotchi:
• Feed it a meal or a snack
• Play a game with it and earn points to spend at the shop for items
• play with the items you get from the shop
• clean up the Tamagotchi's poop
• Discipline it when it is sad or bad
• Interact with other Tamagotchis by connecting (on certain Tamas)
• go to work/school/pre-school (only on the Tamagotchi V4)
• You also need to check it's health and stuff
• If you take care of your Tamagotchi, It will grow and you can get secret characters sometimes too.
• But don't let your Tamagotchi die!
here are some pictures of Tamagotchis:
Version 1 Version 2 Version 3 Version 4
you could buy one if you really wanted one. But if your clueless about what tamagotchis are and this doesn't help, do some research before you buy.