Normal Load: Normal load will write information to the database log file so that if any recorvery is needed it is will be helpful. when the source file is a text file and loading data to a table,in such cases we should you normal load only, else the session will be failed.

Bulk Mode: Bulk load will not write information to the database log file so that if any recorvery is needed we can't do any thing in such cases.

compartivly Bulk load is pretty faster than normal load.