The IRS considers almost all your income as taxable, here is a standard list of compensation items...
- Basic salary
- Call back, standby and overtime income
- Airfare allowances and home leave
- Administration allowances
- Transportation and internet allowances
- Education assistance
- Settling-in allowance
- All other cash or benefits received in-kind
Examples of income that generally aren't taxed...
- Reimbursement of business expenses
- Moving expenses as long as they are dollar for dollar. A lump some that you don't have to account for can be considered taxable income.
- Living away from home expenses