>Why general field is not good thing?

For a lot of reasons.
1. A general field is bound to an external program. If the external program is not installed on a PC, or you don't have the correct version of the external program installed, you're stuck.
2. Memory bloat. A picture which is 100k as a separate file, can occupy as much as 500k in a general field
3. It's a real PITA to get the data out of the general field again.

To sum up: Use separate files, and only store the name of these external files in a text or memo field. General fields seemed like a good idea when they came, but experience has showed that they are nothing but trouble.