TAX + Subsidy 

Funds provided by taxation have been used by states and their functional  equivalents throughout history to carry out many functions. Some of  these include expenditures on war, the enforcement of law and public  order, protection of property, economic infrastructure (roads, legal  tender, enforcement of contracts, etc.), public works, social  engineering, and the operation of government itself. Most modern  governments also use taxes to fund welfare and public services. These  services can include education systems, health care systems, pensions  for the elderly, unemployment benefits, and public transportation.  Energy, water and waste management systems are also common public  utilities. Colonial and moderning states have also used cash taxes to  draw or force reluctant subsistence producers into cash economies.
Governments use different kinds of taxes and vary the tax rates. This is  done to distribute the tax burden among individuals or classes of the  population involved in taxable activities, such as business, or to  redistribute resources between individuals or classes in the population.  Historically, the nobility were supported by taxes on the poor; modern  social security systems are intended to support the poor, the disabled,  or the retired by taxes on those who are still working. In addition,  taxes are applied to fund foreign and military aid, to influence the  macroeconomic performance of the economy (the government's strategy for  doing this is called its fiscal policy - see also tax exemption), or to  modify patterns of consumption or employment within an economy, by  making some classes of transaction more or less attractive.
A nation's tax system is often a reflection of its communal values or  the values of those in power. To create a system of taxation, a nation  must make choices regarding the distribution of the tax burden — who  will pay taxes and how much they will pay — and how the taxes collected  will be spent. In democratic nations where the public elects those in  charge of establishing the tax system, these choices reflect the type of  community which the public wishes to create. In countries where the  public does not have a significant amount of influence over the system  of taxation, that system may be more of a reflection on the values of  those in power.
The resource collected from the public through taxation is always  greater than the amount which can be used by the government. The  difference is called compliance cost, and includes for example the  labour cost and other expenses incurred in complying with tax laws and  rules. The collection of a tax in order to spend it on a specified  purpose, for example collecting a tax on alcohol to pay directly for  alcoholism rehabilitation centres, is called hypothecation. This  practice is often disliked by finance ministers, since it reduces their  freedom of action. Some economic theorists consider the concept to be  intellectually dishonest since (in reality) money is fungible.  Furthermore, it often happens that taxes or excises initially levied to  fund some specific government programs are then later diverted to the  government general fund. In some cases, such taxes are collected in  fundamentally inefficient ways, for example highway tolls.
Some economists, especially neo-classical economists, argue that all  taxation creates market distortion and results in economic inefficiency.  They have therefore sought to identify the kind of tax system that  would minimize this distortion. Also, one of every government's most  fundamental duties is to administer possession and use of land in the  geographic area over which it is sovereign, and it is considered  economically efficient for government to recover for public purposes the  additional value it creates by providing this unique service.
Since governments also resolve commercial disputes, especially in  countries with common law, similar arguments are sometimes used to  justify a sales tax or value added tax. Others (e.g. libertarians) argue  that most or all forms of taxes are immoral due to their involuntary  (and therefore eventually coercive/violent) nature. The most extreme  anti-tax view is anarcho-capitalism, in which the provision of all  social services should be a matter of voluntary private contracts.
Subsidy

Advantages
- reduces cost of production
- releases resources to be used for other purposes e.g expansion (increased supply)
- increases the firms competitive edge in terms of prices. With  subsidies they are able to cover cost without making their products  unaffordable.
Disadvantages
- It increases dependence of firms and hence, might not provide motivation necessary for increasing efficiency and supply