The UN established specialised agencies in order to tackle problems faced by countries in crisis. Four of these agencies are Food and Agriculture Organisation (FAO), World Food Programme (WFP), United Nations Children's Fund (UNICEF) and World Health Organisation (WHO).
The FAO's main concern is to increase the amount and quality of food which people in developing countries receive.
It works with local farmers to try to improve the methods they use, introduces new farming techniques and teaches them about the benefits of using fertilisers and irrigation.
In Namibia, the FAO is helping farmers to grow wild fruit trees to benefit their local economy, by teaching them how to harvest, store and market the fruit products.
Local women now take part in the project and have learned how to make and sell jam and juice from the fruit. The scheme has supplemented the income of local people according to the FAO.
The World Food Programme was established by the FAO and United Nations General Assembly in the 1960s. WFP is the world’s largest humanitarian agency fighting hunger worldwide.
It responds to emergencies, aiming to save lives by getting food to the hungry fast. It also works to help prevent hunger through programmes that use food as a basis for building assets, spreading knowledge and encouraging stronger communities that are more food secure.
On average, WFP reaches more than 90 million people with food assistance in 80 countries each year.
Unicef works to improve the lives of children in developing countries. It funds programmes to provide schools, teachers and equipment so that children can grow up able to read and write and provide for themselves. Unicef receives no funding from the UN. Unicef relies entirely on voluntary donations.
The organisation works in more than 190 countries and delivers life-saving help for children when emergencies strike. For example, Unicef UK is raising funds to help tackle the Ebola crisis in West Africa.
During the Commonweath Games opening ceremony in Glasgow, Unicef UK received £3.7m in donations.
WHO is the UN's health arm. It aims to improve the health of people in developing countries. WHO trains local people to become nurses and health care workers in their own country. The organisation also works to eliminate diseases such as malaria by making people aware of how to avoid contracting it.
In August 2014, WHO developed a roadmap for halting the Ebola outbreak and treating people infected with the virus. This is estimated to cost over $490 million. WHO is seeking contributions to purchase supplies such as personal protective equipment, chlorine and motorcycles for contact tracing.