KYC is short for Know Your Customer. To put it simply, it's the process of a business verifying the identity of its clients. When you first registered to Bitcoin.co.id a month ago for example, you had to fill in some informations such as identity card or passport numbers, your name, address, etc. But now, you only need to fill in your username, email, password, and phone number for sms verification to protect your account. No need to give out personal details