If I were talking about a web hosting server, would there be a maximum limit of files per directory?
It comes down to filesystem in most cases:
NTFS has a maximum number of files per volume, not directory: 4,294,967,295 (via Satanicpuppy)
ext3 originally had the same limit at ext2 (31,998). However, if your distro supports dir_index I believe the only limit is your machine's ram with deteriorating performance as the directory grows beyond 100k files.
not quite sure what you mean. If you mean can a host set up a maximum file usage then yea. My host, hostgator has a 50,000 inode limit or something like that. that means any more than 50,000 files and I get banned.
If you mean like filesystems if you can set that up quotas. You can in Linux, I am sure there must be some mechanic for windows as well.