Hi,
You can take live backup's on operating database's, but they have to be "Backup Aware" i.e. a command given to the DB Engine that causes it to stop updating the main DB files & all edits, adds & deletes are routed to temp work files, which hold the transactions until the backup of the snapshot image is complete. After the backup is complete the temp files then update the main DB in the background.

Foxpro does not have this inbuilt ability, all you will get is a desync'ed corrupted mess if you try to retore.
Most Backup software app's have plugins for each different DB app, this is what the guy is getting confused with. One plugin does not suit all.

Also if an SQL query is issued the DB Engine will automatically do the required joins between the Main DB files & the temp files, to give the correct results, even though the backup is in progress.