"SAFU" in the context of Binance refers to the "Secure Asset Fund for Users". It was introduced by #Binance as a means to protect users and their funds in extreme cases.
This fund is an emergency insurance, so to speak, which is reserved and stocked up by Binance over time. As mentioned, it is primarily used to cover potential losses from unforeseen events such as hacks.
The term #SAFU itself comes from a meme within the crypto community. Originally, it was a humorous misspelling of the word "safe" in a video and later adopted by Binance's CEO #ChangpengZhao (CZ) in the announcement of the fund.
As of my last update, Binance commits 10% of all trading fees received into SAFU to offer protection to users and their funds in extreme cases. This amount is stored in a separate cold wallet.
Binance is regarded as a safe exchange that provides account protection for users with security features like the use of Two Factor Authentication (2FA).
After the last major security breach in 2019, Binance has been relatively safe and secure for trading. Additionally, they try to cover the losses of assets for their users out of their own pockets, which gives a higher level of integrity for the platform.
According to Binance, one of their goals is to never use SAFU, they hope to achieve this by providing the most secure crypto platforms possible for all of their users, whether centralized or decentralized.