Javascript / JQuery处理并发/异步调用和数据竞争

I am currently trying to search a bit about how Javascript handles data race in parallel or asynchronous calls. As far as I'm concerned, the only way to make asynchronous stuff on my code is by AJAX calls (correct if I'm wrong!), but I suppose that if there is another way, it will be handled likewise.I am currently trying to search a bit about how