These are your employment taxes. The SS wage base is what goes into calculating your SS benefits (etc.) and the medicare wage base goes for medicare, veterans (etc).
Assuming you don't have certain health or other plans for your business, your SS and medicare wages are typically just equal to your gross pay. After a little over $100,000 in compensation is paid to any one employee, you'll no longer be subject to the 12.4% SS tax for that employee's wages. There is no limit for the medicare portion. Laws have also raised these percentages very recently for high income taxpayers, so the above doesn't apply to certain people.
These employment taxes are the equivalent of self-employment taxes paid by business owners using Schedule C or having a partnership interest.
Both of these taxes are paid 50/50 by the employee and employer. The employees' portion gets withheld from their paychecks while the employer remits their share, along with the employees', according to their payroll tax deposit schedule and method (quarterly, monthly, semi-weekly, next day depositors with deposit coupons, EFTPS payments, and payments with quarterly 941 returns).
Other employer taxes consist of your federal and state unemployment taxes These taxes are not paid at all by the employee.
To sum up, employer taxes are:
6.2% SS tax on gross wages
1.45% Medicare tax on gross wages
0.8% Federal unemployment up to $7,000 in wages
xxx% State unemployment at varying rates, usually near 2.7% and up to around $9,000 in wages.
Employee taxes are: