This map is on Language Log today. It shows south Asia with all the countries and states labeled with the local script. I count 13 scripts.
All of the scripts, except Arabic and Chinese, are descended from Brahmi. There are many more Brahmi-derived scripts in southeast Asia, such as Thai, Khmer, and Javanese. And although this map shows all the scripts of south Asia in current use (I think), there are many others that are seldom used - for instance Tulu, Grantha and many others.
I have often wished English had that beautiful script. Then I have wondered if their script looks, to Asians, like our letters look to us (mundane); and yet do our letters look beautiful to them? I doubt it, but I have wondered. Perhaps I will ask my Chinese friend, though I suspect she has known English for too long now.
Make that 14. I just learned that India has yet another script: Manipuri, apparently the script for the official language of the state of Manipur, the green state on the far right. It's not one of the 9 scripts on the currency.
Japanese has 46 hiragana and 46 katakana - the katakana might help you sound out the odd word borrowed from English. But there's also the 2000 kanji - Chinese characters. It's pretty much impossible to read anything if you don't know them.
On the other hand, the pronunciation is quite simple!
On a computer, one can type the words phonetically using Pinyin or another romanization method, so you can use a keyboard with around the same number of keys as a western keyboard.
But there are other methods. I remember seeing, in the movie You Only Live Twice, a brief shot of a Japanese typewriter with a whole lot of keys.
Most people these days type Japanese and Chinese with a standard computer keyboard. As gooofy says, the typing is usually based on some kind of romanization scheme, i.e., representing characters by how they are pronounced and written in the Latin alphabet. Most modern operating systems (at least Windows and MacOS) come with the ability to add different keyboard layouts. (If somebody is interesting, send me a PM.) I have seen some schemes that involved counting and categorizing strokes, but I am not relaly familiar with them. The only manual character typewriters had many, many keys, and aren't really used anymore.
Well, Japan, unfortunately, is out of the picture for me now. Too bad! I was looking forward to studying the language. I think the best way to learn a language is by being in the country and having to communicate.