In most developed countries, income tax is the primary means governments have of raising revenue for themselves. Since it is paid by almost everyone, it also tends to be the most politically sensitive tax and arguments about its appropriate level frequently feature in political debates.
In almost all cases, income tax is applied in a series of graduated bands, meaning that as a citizen’s income rises, his income above certain threshold values would be taxed at a gradually increasing rate. At very high incomes, it is even possible that the majority of any income gains a person benefits from will go to the government rather than to the income earner.
The existence of income tax necessitates an elaborate system of reporting and checking through which citizens declare their annual income to the government and those declarations are scrutinised to make sure that they are accurate. Penalties for untruthfulness or evasion of tax responsibilities include fines and imprisonment. In some cases, income tax responsibilities are handled by employers, who deduct the appropriate amounts from their employee’s wages before the employee receives them and forward this money to the government. In this context, it may not be necessary for the employee to file a personal tax return with the government because it will all be taken care of automatically.