What is msgstore and what is it for

I had about 4-5 msgstore files in my cell file 2 days ago an they are msgstore files The files inside this folder are the recent file backups The latest backup must be named something like ' crypt12' or 'msgstore msgstore files Same here db crypt 14 files keep downloading themselves there are 6 of them Is it a malware or something? Also when I opened it

guitar nut slot files The file like : * Those are your Database files are often small