but some time after WWII (I don't remember the exact dates) Japan and Mainland China adopted a simplified form.
I lived in Taiwan when I was younger and studied Mandarin there, and can read a limited vocabulary of traditional Chinese characters. I don't know enough about the history of simplified characters in Japan, but it doesn't seem to me that they are as widely used (with a few exceptions like 国) as traditional forms. Maybe someone knows the history?
Also, regarding this statement:
臺 (Korea/Taiwan) 台 (Japan/China)
In Taiwan, the latter form of tai (台) is used 99% of the time in colloquial, news, and signage. The complex form (臺) AFAIK is used almost exclusively in certain government situations (e.g. the name of a central government bureau) or on money. Street signs for famous buildings all use 台, i.e. 台北101, 台北松山機場, etc.
I lived in Taiwan when I was younger and studied Mandarin there, and can read a limited vocabulary of traditional Chinese characters. I don't know enough about the history of simplified characters in Japan, but it doesn't seem to me that they are as widely used (with a few exceptions like 国) as traditional forms. Maybe someone knows the history?
Also, regarding this statement:
臺 (Korea/Taiwan) 台 (Japan/China)
In Taiwan, the latter form of tai (台) is used 99% of the time in colloquial, news, and signage. The complex form (臺) AFAIK is used almost exclusively in certain government situations (e.g. the name of a central government bureau) or on money. Street signs for famous buildings all use 台, i.e. 台北101, 台北松山機場, etc.