A W-2 employee is an employee whose taxes are withheld by the employer and whose earnings are reported to the IRS at the year-end via a W-2. The W-2 employee completes a form W-4 at the beginning of their employment to instruct the employer on how to withhold taxes. This eliminates any possible issues that may arise with the IRS regarding employment status.

(source: Dice.com)

Indicates that the employer would prefer to deal directly with another corporation. The main reason for this preference is to avoid some of the potential liability that might exist in dealing with an independent contractor on a 1099 basis. This would include corporations dealing directly with other corporations or corporations dealing with individuals who have incorporated.

(source: Dice.com)

A 1099 employee is in most cases a temporary employee (technically, not even an “employee”). Because they are not permanent, they do not need to complete a W-4 or have the employer withhold taxes. They are responsible for paying their taxes directly to the IRS. The IRS requires that the employer report the earnings paid on a form 1099. The IRS would rather put the burden of tax withholding on the employer and therefore has fairly stringent rules regarding when someone can be considered a 1099 employee.

(source: Dice.com)