Estate Tax-Federal Estate Tax

Flattruth asked:


I need clarification regarding capital gains tax for a real estate transaction. I read generally 6% of selling price of the property or fair market value of the property received in an exchange transaction. Does this mean 6% of the difference between sell price and previous buy price (the profit) or 6% of gross sale price (which is a lot!)?

That is, does capital gains have a different meaning than the normal?
The definition of Capital gains I know:
Final price minus buying price = Capital gains

Is capital gains definition different for this transaction?

Nick Lee