What is thread safe and non-thread safe in PHP and how does it affect work?

Hello everyone! I've just started learning PHP more deeply and came across the terms "thread safe" and "non-thread safe" when downloading PHP distributions. Honestly, I'm confused. I'm writing a regular web application on PHP + Apache (mod_php). I have a simple script that counts page visits in a file: ```php ``` It seems to work fine, but I've read that if you use thread safety, there can be problems with race conditions and variables can "overlap" between threads. And if non-thread safe, everything works faster but may crash. I don't understand: which option should I choose for