difference between gold fund n gold thru commodity exchange

whats the difference between gold purchased thru gold fund, n what if purchased thru commodity exchange.
can v hold gold bought thru exchange for a year long period n whats the cost of such holding.
Answer:
u talking about trading gold prices, its short term u can lose or gain, its speculation.

if u want to invest for long term 1-3 years hold it till u see it reach peak and then sell then ETF is better.

If u want to hold it longer buy physical gold