The Pocket Pikachu, (or PoPi), is not an ordinary Tama. It has a built in "pedometer". For the ones who aren't that smart (that includes me), a "pedometer" is a machine that counts your footsteps. As I said, it is built in in the PoPi.
Pikachu himself, is an "electric mouse", whatever that may be. He's a pokémon. Just look at the pictures and decide for yourself what he is. You don't really have to take care of it like a Tama. So you don't have to scoop his poop, you don't have to feed it, etc. etc. So you would think it's for lazy people. 
It's not.
You have to walk with Pikachu. The pedometer counts your footsteps, and if you walk 100 steps, you will get 5 watts. So, you get your watts faster if you jog or run. Pikachu will walk with you. The screen is normaly blank. (This is a battery saving function) But don't worry, if you press start, the screen will turn back on. So, if you are jogging, and you press start to see Pikachu, he will be running with you, or skateboarding, or riding a bike, or driving a car and so on. He is real fun to watch.
But these Watts have other functions rather than to make Pikachu walk. You can give the acquired (did I spell that right?) Watts to Pikachu. According to the amount of Watts you give him, he will be angry, bored or he will love you. He may do a somersault, or write you a letter, or other kinds of very cute stuff. If you don't walk with him, he will get angry and turn his back on you, or even run away.
But you have to be real mean before that happens, so don't worry.
This is the front of the Pocket Pikachu package.
This is the back. I don't know why I'm showing this, but why not?
This is the case itself. This is Pikachu's "home". The PoPi is the first electronic pet made by Nintendo. That's probably why the case looks like a small gameboy. It has a beltclip on the back, so you can fasten it on your belt. Very handy
Now I know this isn't my best pic, it's still real handy. Now I can explain the icons easier. (Not that they're that hard to guess)
Well, most of the things speak for themselves. I'll explain the first icon, the little clock. If you select the clock, you will see a screen where they tell you if the alarm is set, and if the sound is on or off, (The sound is real funny, it makes a short, chirpy "beep" sound. When you walk, you hear "beep" "beep" "beep". The sound stops when the screen goes blank.) Then next comes the gift icon. This is used to give the Watts to your Pikachu. When you select this, you get a screen that tells you how many Watts you have to give Pikachu. Then there are three 0's, and the first one is blinking. You can fill in how many Watts you want to give him, and then you press A. There will then be a sign saying GIVE? If you want to give, press A, if you don't press B Quite logical, isn't it?
If you press "select", you will get a screen saying Pikachu's mood, and how many steps you have already taken. The moods are in Japanese, so here is the translation. (See above)
He's so cute!
