From my own experiences with computers (good couple of decades), the most-common reasons for computers to become unresponsive is either because of a badly coded program (causing memory leaks), lack of sufficient RAM to handle all of the simultaneous processes that were loaded, or sometimes just plan over-heating.
Software typically won't tell you what causes your system to hang, but you can narrow it down, filtering out the root-causes that might be affecting performance, just running one program at a time instead of several. Hopefully it's not a critical hardware-issue (such as failing hard-drive that might eventually crash; because such errors typically wipe a lot of the data that you might have, and are very expensive to repair, due to needing to go through a specialised recovery service such as OnTrack if it does happen, and you might expect only between 10% to 50% of your files being recovered from a crashed hard-drive, if you're lucky).
I don't have much information about your issue but I would probably recommend running some diagnostics-tests on your system in order to measure performance for each of the critical-areas of functioning.
Kamryn wrote:
Software-wise, can I tell what causes my computer to freeze?
OS: Ubuntu 17.10 (x64)
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