The taxation system in the United Kingdom is defined by a personal allowance plus three bands: basic, higher and additional. Other taxes like the National Insurance Contribution (NIC) sum up to the total deductions. More information is available at the government website.
In the United States the taxes are both Federal and from the states. The federal government imposes seven different tax brackets plus the Social Security and Medicare deductions. Citizens are taxed worldwide and must submit the forms in April. The IRS website explains the process.
The German taxation system consists in progressive brackets plus the Solidarity Surcharge (Solidaritätszuschlag). Taxes are imposed by both the federal government, the states and the municipalities. Complete information can be found at the government website.
Income taxes in India are applicable to any activity other than agirculture, and follows the regulation stablished in 2010. Up to four tax rates are imposed over the income, with a maximum of 30% deduction. The Income Tax Department is the government division which controls the tax policies.
Personal earnings in Australia are subject to the taxes collected by the Australian Taxation Office. Five tax rates plus additional charges like the Medicare levy may eat up to 50% of the gross income. Minors and non-residents follow a different tax system.
Resident taxpayers in Brazil are imposed to five tax brackets, the top one representing a 27.5% deduction on gross salary income. Other taxes like INSS (social security system) are also imposed. The government division responsible for tax collection is the Secretaria da Receita da Fazenda.