http://wiki.answers.com/Q/What_is_the_difference_between_a_salary_and_a_wage

earning - is the Present Participle of the verb "to earn"
as for "earningS", here are a few random definitions:

Wages, money earned, income; Business profits; Gains on investments; returns

Profit available to ordinary shareholders, after all operating expenses, interest charges, taxes and preference dividends have been deducted. ...

The net income of a company during a specific period. Generally, but not necessarily, referring to after-tax income.

The amount of profit a company realizes after all costs, expenses and taxes have been paid. See also "net earnings."

Revenues minus expenses and taxes. Also called income.

The total amount earned, usually by a worker as wages, or by a firm as profits.

Income received by labor for its contribution to production. It consists of wages, salaries, and benefits paid to employees plus the income of ...

A corporation's profits. An earnings report is a statement a company issues to shareholders and to the public declaring its current profits on ...

This figure is calculated by dividing profits or losses attributable to members of the Company by the number of shares in issue.

The same as net income or net profit.