Some of the terms used in ETFs trading:
Ask price - Lowest price any seller is willing to accept for a
security at a given time.
Bid price - Highest price that any buyer is willing to pay for
a security at any given time.
Value - Describes stocks in a market which have relatively low
Price-to-Earnings or other valuation ratio. Typically slow growth, high dividend
companies. Typically safer than growth stocks with high valuations.
Price spread - The difference between the "bid" and "ask" price
on a stock or ETF.
Naked options trading is very risky - many people lose money trading them. It is recommended contacting your broker or investment professional to find out about trading risk and margin requirements before getting involved into trading uncovered options.