The ransomware actually locks up all the files in your computer and demands $300 in bitcoin in order to regain control.
勒索软件实际上锁定了您计算机中的所有文件,并要求支付 300 美元的比特币才能重新获得控制权。
英语百科
File locking
(重定向自Lock file)
File locking is a mechanism that restricts access to a computer file by allowing only one user or process access at any specific time. Systems implement locking to prevent the classic interceding update scenario, which is a typical example of race condition, by enforcing the serialization of update processes to any given file. The following example illustrates the interceding update problem: