Don't delete files casually. In fact, disk C is generally a system disk, which is only used to install the system. However, because the default installation path of general software is disk C, you will install it as long as you install the software, so the available space of disk C (not the capacity of disk C) is of course getting smaller and smaller. If it's no trouble, uninstall all the software and install it on other disks, but it's not necessary, just pay attention when installing the software in the future. When choosing the installation path, just browse and change to another disk, such as office, antivirus software, qq, real, etc. In addition to the driver, you can install it on other disks and turn off the system restore function, but I suggest that you keep the system restore function of disk C (if it is still too big, you can clean the restore point regularly, and the right keyboard symbol has this function, click "Other Options" in "Disk Cleanup" just in case). For general junk files and things generated online, you can use a super rabbit or an optimization master to clean the disk regularly, which is nothing, at least it can keep the C disk from getting bigger.