On a payroll register sheet, it has " taxable earnings", " unemploy. comp. and soc. sec. what doesit mean?

Sounds like you are asking what the earnings amounts of these taxes are. Taxable earnings apply to all taxes and the earnings are the compensation you make that is applicable to those taxes. Different taxes have different earnings limits.

Social Security is taxable up to102,000 for 2008 at a rate of 6.2%

Medicare taxes have no limit and are taxable at 1.45%.

Unemployment for state is taxable up to the state limit and it differs from state to state. Each employer is assigned a different rate based on how much the unemployment claims are versus the amount of unemployment tax paid for a particular employer. When you file your state UC return it will have your rate and the amount of taxable earnings. If you don't know it already contact the state and they will tell you.

Unemployment for federal is taxable for the first 7,000 of earnings at a tate of .008 percent which is 56.00 per year.

Keep in mind that certain deductions lower the earnings for certain taxes. For example, 401k decreases earnings for federal taxes and certain medical deductions decrease earnings for social security and medicare.

If you are paying employees in the USA, their earnings are "taxable earnings", and there are taxes to deduct that involve "unemployment compensation" and "social security".

NO HELP ON HOMEWORK.

Taxable earning are just that, earnings that are taxable. Some earnings, by law, are not, such as those earnings that are funneled into a 401-K or other exempt retirement fund. Other tax exempt earnings for tax filing purposes may be social security disability, social security retirement and child support.