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What is the difference between 'ingin' and 'mau'?

my opinion is willingness (kemauan) different meanings with desire (keinginan). If the will be followed by action, desire is the interest in something but no action followed. from explain above, we can get a conclusion that ingin dan mau diferent.
"ingin" means we are only interested but not necessarily performed. but when "mau" means that we are interested in and act real.

i'm so sorry if my English is so bad. i hope u understand what i mean n my explain :)

Well I think "ingin" is more formal than "mau"...

We use "mau" in everyday speech....
* I can't imagine the president use the word "mau" in his speech*
Hope this is helpful ^0^,

It's same. You can use both when you want something, but see the example
Saya ingin pergi ke paris (It's like I want. but still don't know I will make it real or not)
Saya mau pergi ke paris (I want, and I will go to paris)

mau: want, will

Clover explanation is just perfect.

"ingin" means want, will.
"mau" means want or will too. but it also has other meaning. "mau" can be definite to "willingness" or "readiness"