An explosion at the Chernobyl Nuclear Power Plant in 1986 spread a radioactive cloud over large parts of the Soviet Union, now the territories of Belarus, Ukraine and the Russian Federation. Nearly 8.4 million people in the three countries were exposed to the radiation.

The Soviet Government acknowledged the need for international assistance only in 1990. That same year the General Assembly adopted resolution 45/190, calling for “international cooperation to address and mitigate the consequences at the Chernobyl nuclear power plant.” That was the start of the United Nations' involvement in the Chernobyl recovery. An Inter-Agency Task Force was established to coordinate the Chernobyl co-operation. In 1991 the UN created the Chernobyl Trust Fund - currently under the management of the Office for the Coordination of Humanitarian Affairs (OCHA). Since 1986, the UN family of organizations and major NGOs have launched more than 230 different research and assistance projects in the fields of health, nuclear safety, rehabilitation, environment, production of clean foods and information.

In 2002 the United Nations announced a shift in the Chernobyl strategy, with a new focus on a long-term developmental approach. UNDP and its regional offices in the three affected countries took the lead in the implementation of the new strategy. There is still a great deal of work that needs to be done in the affected region. To provide support to international, national and public programmes targeted at the sustainable development of these territories, in 2009 UN launched the International Chernobyl Research and Information Network (ICRIN).

On 8 December 2016 the United Nations General Assembly adopted a resolution designating 26 April as International Chernobyl Disaster Remembrance Day. The General Assembly recognized that, “three decades after the Chernobyl disaster, the still-persistent serious long-term consequences thereof, as well as the continuing related needs of the affected communities and territories,” and invited “all Member States, relevant agencies of the United Nations system and other international organizations, as well as civil society, to observe the day.”

2017 Theme: Optimize the collection and use of OSH data Every day, 6,300 people die as a result of occupational accidents or work-related diseases – more than 2.3 million deaths per year. 317 million accidents occur on the job annually; many of these resulting in extended absences from work. The human cost of this daily adversity is vast and the economic burden of poor occupational safety and health practices is estimated at 4 per cent of global Gross Domestic Product each year.

The ILO’s campaign for the 2017 World Day for Safety and Health at Work focuses on the critical need for countries to improve their capacity to collect and utilize reliable occupational safety and health (OSH) data.

The United Nations 2030 Agenda for Sustainable Development adopted on September 25, 2015 encompasses a global plan of action with specific targets to end poverty, protect the planet, and ensure prosperity for all. With its adoption, the capacity to collect and utilize reliable OSH data has also become indispensable for countries to fulfil their commitment to implement and report on some of the agenda’s 17 sustainable development goals and their targets.

The World Day for Safety and Health at Work is an annual international campaign to promote safe, healthy and decent work. It is held on 28 April and has been observed by the International Labour Organization (ILO) since 2003.

A national occupational safety and health culture is one in which the right to a safe and healthy working environment is respected at all levels, where governments, employers and workers actively participate in securing a safe and healthy working environment through a system of defined rights, responsibilities and duties, and where the highest priority is accorded to the principle of prevention.

The Conference of the States Parties at its Tenth Session paragraph 23.3 of C-10/5, dated 11 November 2005) decided that a memorial Day of Remembrance for all Victims of Chemical Warfare would be observed on 29 April each year — the date in 1997 on which the Chemical Weapons Convention entered into force.

This commemoration will provide an opportunity to pay tribute to the victims of chemical warfare, as well as to reaffirm the commitment of the Organization for the Prohibition of Chemical Weapons (OPCW) to the elimination of the threat of chemical weapons, thereby promoting the goals of peace, security, and multilateralism.

The Third Review Conference of States Parties to the Chemical Convention held 8-19 April 2013 in the Hague, the Netherlands, adopted by consensus a political declaration that confirms the “unequivocal commitment” of the States Parties to the global chemical weapons ban, and a comprehensive review of CWC implementation since the last Review Conference in 2008 that also maps out the OPCW’s priorities for the coming five years.

Why International Jazz Day?

Jazz breaks down barriers and creates opportunities for mutual understanding and tolerance; Jazz is a vector of freedom of expression; Jazz is a symbol of unity and peace; Jazz reduces tensions between individuals, groups, and communities; Jazz fosters gender equality; Jazz reinforces the role youth play for social change; Jazz encourages artistic innovation, improvisation, new forms of expression, and inclusion of traditional music forms into new ones; Jazz stimulates intercultural dialogue and empowers young people from marginalized societies.

In November 2011, the UNESCO General Conference proclaimed PDF document 30 April as "International Jazz Day". The Day is intended to raise awareness in the international community of the virtues of jazz as an educational tool, and a force for peace, unity, dialogue and enhanced cooperation among people. Many governments, civil society organizations, educational institutions, and private citizens currently engaged in the promotion of jazz music will embrace the opportunity to foster greater appreciation not only for the music but also for the contribution it can make to building more inclusive societies.

"On this Day of Vesak, let us celebrate the wisdom of Lord Buddha by taking action for others with a strong spirit of solidarity."

—— UN Secretary-General, António Guterres

"Vesak", the Day of the Full Moon in the month of May, is the most sacred day to millions of Buddhists around the world. It was on the Day of Vesak two and a half millennia ago, in the year 623 B.C., that the Buddha was born. It was also on the Day of Vesak that the Buddha attained enlightenment, and it was on the Day of Vesak that the Buddha in his eightieth year passed away.

The General Assembly, by its resolution 54/115 of 1999, recognized internationally the Day of Vesak to acknowledge the contribution that Buddhism, one of the oldest religions in the world, has made for over two and a half millennia and continues to make to the spirituality of humanity. This day is commemorated annually at the UN Headquarters and other UN offices, in consultation with the relevant UN offices and with permanent missions, which also wish to be consulted.

Many countries depend heavily on tuna resources for food security and nutrition, economic development, employment, government revenue, livelihoods, culture and recreation.

At present more than 80 States have tuna fisheries, thousands of tuna fishing vessels operate in all the oceans and tuna fishery capacity is still growing in the Indian and Pacific Oceans.

We observe World Tuna Day to highlight the importance of sustainably managed fish stocks in achieving the 2030 Agenda for Sustainable Development.

The Day was designated in a 2016 resolution of the General Assembly.

World Press Freedom Day was proclaimed by the UN General Assembly in December 1993, following the recommendation of UNESCO's General Conference. Since then, 3 May, the anniversary of the Declaration of Windhoek is celebrated worldwide as World Press Freedom Day.

It is an opportunity to:

celebrate the fundamental principles of press freedom; assess the state of press freedom throughout the world; defend the media from attacks on their independence; and pay tribute to journalists who have lost their lives in the line of duty.

2018 Theme: Keeping Power in Check: Media, Justice and The Rule of Law

The theme of the 2018 celebration highlights the importance of an enabling legal environment for press freedom, and gives special attention to the role of an independent judiciary in ensuring legal guarantees for press freedom and the prosecution of crimes against journalists.

At the same time, the theme addresses the role of the media in sustainable development, especially during elections - as a watchdog fostering transparency, accountability and the rule of law. The theme also aims to explore legislative gaps with regard to freedom of expression and information online, and the risks of regulating online speech.

Within the 2030 Agenda for Sustainable Development, the contribution of journalists and media workers is most associated with Sustainable Development Goal (SDG) 16 of peace, justice and strong institutions. In order to reach this goal, effective, accountable and transparent institutions at all levels must be developed, and press freedom is essential for this.

By resolution 59/26 of 22 November 2004, the UN General Assembly declared 8–9 May as a time of remembrance and reconciliation and, while recognizing that Member States may have individual days of victory, liberation and commemoration, invited all Member States, organizations of the United Nations System, non-governmental organizations and individuals to observe annually either one or both of these days in an appropriate manner to pay tribute to all victims of the Second World War.

The Assembly stressed that this historic event established the conditions for the creation of the United Nations, designed to save succeeding generations from the scourge of war, and called upon the Member States of the United Nations to unite their efforts in dealing with new challenges and threats, with the United Nations playing a central role, and to make every effort to settle all disputes by peaceful means in conformity with the Charter of the United Nations and in such a manner that international peace and security are not endangered.

By resolution 59/26 of 22 November 2004, the UN General Assembly declared 8–9 May as a time of remembrance and reconciliation and, while recognizing that Member States may have individual days of victory, liberation and commemoration, invited all Member States, organizations of the United Nations System, non-governmental organizations and individuals to observe annually either one or both of these days in an appropriate manner to pay tribute to all victims of the Second World War.

The Assembly stressed that this historic event established the conditions for the creation of the United Nations, designed to save succeeding generations from the scourge of war, and called upon the Member States of the United Nations to unite their efforts in dealing with new challenges and threats, with the United Nations playing a central role, and to make every effort to settle all disputes by peaceful means in conformity with the Charter of the United Nations and in such a manner that international peace and security are not endangered.

World Migratory Bird Day 2018

"Unifying our Voices for Bird Conservation"

On 26 October 2017 in the margins of the CMS COP12 in Manila, Environment for the Americas (EFTA), the Convention on Migratory Species (CMS) and the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA), announced an innovative partnership to increase awareness of the plight of migratory birds around the world. The new partnership formally unites two of the world's largest bird education campaigns, International Migratory Bird Day (IMBD) and World Migratory Bird Day (WMBD) in a bid to strengthen global recognition and appreciation of migratory birds and highlight the urgent need for their conservation. From 2018 onwards, the new joint campaign will adopt the single name of "World Migratory Bird Day" and major events to celebrate the day will be organized twice a year, on the Second Saturday in May and in October.

The year 2018 marks a new start for World Migratory Bird Day as it now unifies the planet’s major migratory bird corridors, or flyways, namely the African-Eurasian, the East Asian-Australasian, and the Americas flyways. Furthermore, to make celebrations even more successful and relevant to bird supporters all over the world, WMBD will now have two peak celebration days in the year - the second Saturdays of May and October - and can in addition still also be celebrated all around the year, whenever migratory birds are present in a given locality.

Therefore 2018 is an important transition year in the history of World Migratory Bird Day. Bringing together even more people around the world, WMBD aims to reach out to a broader audience and amplify its message for bird conservation. As a new global platform that unifies efforts worldwide, WMBD will be reinforcing education and awareness-raising about the need to protect migratory birds and their habitats - at all different levels, in all parts of the world.

WMBD dedicates 2018 to its major flyways and the new inter-flyway cooperation With "Unifying our Voices for Bird Conservation" as its theme for 2018, in the "Year of the Bird", WMBD is focusing clearly and strongly on the development of its new identity and the need for people celebrating WMBD around the world to communicate and learn from each other, across borders, within and between the world's flyways. Through the activities being undertaken on these three flyways and the resulting exchange of information, WMBD wishes to increase the level of awareness about the threats – both general and specific – that birds are facing. By comparing their experiences and concerns, sharing their stories and activities, people around the world will make their voices and actions reach out even further, throughout the flyways, underlying the fact that bird conservation is, indeed, a global issue.

Although families all over the world have transformed greatly over the past decades in terms of their structure and as a result of global trends and demographic changes, the United Nations still recognizes the family as the basic unit of society. The International Day of Families provides an opportunity to promote awareness of issues relating to families and to increase knowledge of the social, economic and demographic processes affecting them.It has inspired a series of awareness-raising events, including national family days. In many countries, this day is an opportunity to highlight different areas of interest and importance to families.

The International Day of Families is observed on the 15th of May every year. Activities include workshops and conferences, radio and television programmes, newspaper articles and cultural programmes highlighting relevant themes.

2018 Theme: “Families and inclusive societies”

This year’s observance will explore the role of families and family policies in advancing Sustainable Development Goal 16 in terms of promoting peaceful and inclusive societies for sustainable development.

International Day of Living Together in Peace 16 May

Living together in peace is all about accepting differences and having the ability to listen to, recognize, respect and appreciate others, as well as living in a peaceful and united way.

The UN General-Assembly, in its resolution 72/130, declared 16 May the International Day of Living Together in Peace, as a means of regularly mobilizing the efforts of the international community to promote peace, tolerance, inclusion, understanding and solidarity. The Day aims to uphold the desire to live and act together, united in differences and diversity, in order to build a sustainable world of peace, solidarity and harmony.

The Day invites countries to further promote reconciliation to help to ensure peace and sustainable development, including by working with communities, faith leaders and other relevant actors, through reconciliatory measures and acts of service and by encouraging forgiveness and compassion among individuals.

May 16 International Day of Light (UNESCO)

Light plays a central role in our lives. On the most fundamental level, through photosynthesis, light is at the origin of life itself. The study of light has led to promising alternative energy sources, lifesaving medical advances in diagnostics technology and treatments, light-speed internet and many other discoveries that have revolutionized society and shaped our understanding of the universe. These technologies were developed through centuries of fundamental research on the properties of light – starting with Ibn Al-Haytham’s seminal work, Kitab al-Manazir (Book of Optics), published in 1015 and including Einstein’s work at the beginning of the 20th century, which changed the way we think about time and light.

The International Day of Light celebrates the role light plays in science, culture and art, education, and sustainable development, and in fields as diverse as medicine, communications, and energy. The will allow many different sectors of society worldwide to participate in activities that demonstrates how science, technology, art and culture can help achieve the goals of UNESCO – building the foundation for peaceful societies.

The International Day of Light is celebrated on 16 May each year, the anniversary of the first successful operation of the laser in 1960 by physicist and engineer, Theodore Maiman. This day is a call to strengthen scientific cooperation and harness its potential to foster peace and sustainable development.

The purpose of World Telecommunication and Information Society Day (WTISD) is to help raise awareness of the possibilities that the use of the Internet and other information and communication technologies (ICT) can bring to societies and economies, as well as of ways to bridge the digital divide.

17 May marks the anniversary of the signing of the first International Telegraph Convention and the creation of the International Telecommunication Union.

2018 Theme: Enabling the positive use of Artificial Intelligence for All

In recent years there has been significant progress in AI technology, made possible by tremendous advances in contributing fields, such as Big Data, machine learning, computing power, storage capacity and cloud computing, among others. AI-based technologies are already emerging as a key component of proactive tools and applications being used to help people lead better lives by improving healthcare, education, finance, agriculture, transportation, and a wide range of other services.

The 2018 theme will focus on the potential of Artificial Intelligence (AI) to accelerate the United Nations Sustainable Development Goals (SDGs).