1. Individual Tax Returns (Form 1040)
2. Corporate Tax Returns (Form 1120)
3. Partnership Tax Returns (Form 1065)
4. Nonprofit Tax Returns (Form 990)

- Simple Individual Tax Returns (Form 1040EZ) for straightforward tax situations with no dependents and basic income sources.

- Complex Individual Tax Returns (Form 1040) including schedules such as Schedule A for itemized deductions, Schedule C for business income, and Schedule D for capital gains.

- Corporate Tax Returns (Form 1120) encompassing details on income, deductions, credits, and taxes for C-corporations.

- Partnership Tax Returns (Form 1065) which outline income, deductions, gains, losses, and credits for partnerships.

- Nonprofit Tax Returns (Form 990) providing information on revenue, expenses, assets, liabilities, and activities of tax-exempt organizations.