Kalendarz jest umownie przyjętą jednostką czasu oraz sposobem jego pomiaru i rozpowszechniania. W pomiarach czasu  kalendarz służy do wyznaczania daty, roku, miesiąca oraz dnia, natomiast zegar służy do mierzenia upływu czasu w godzinach, minutach i sekundach. Nazwa pochodzi od rzymskiego słowa „kalendy” (po łacinie calendae) bądź według innych źródeł od łacińskiego „callendarium” – pierwszego dnia […]


Vienna – the largest city in Austria located on the Danube River. A large administrative, industrial, tourist, academic and cultural hub of international importance. Founded around 500 BC in the process of Celtic expansion, it became a frontier Roman outpost in 15 BC. In 1221, being one of the most important locations of the Holy Roman Empire, it was granted city rights. After the dissolution of this Empire in 1806, the city became the capital of the Austrian Empire and then, until 1918, of the Austro-Hungarian Empire.


The subject of religion is vast and its presence has long occupied an important place in culture and politics and has played a significant role in the development of civilisation. The oldest traces of religion can be found as far back as prehistoric times in the form of cave drawings and burials. According to recent research, the origins of religion date back to Neanderthal times, and it is assumed that its original form was animism, according to which non-human beings such as plants, animals or inanimate objects have a soul. Information on religion is also provided by written works, which began to appear around 4 000 BC. What emerges from them are pictures of established religions, the development of which was influenced by various ancient civilisations. With the help of religion, man tried to comprehend the world and the phenomena around him, such as thunderbolts, death or day and night cycle.


The process of ageing of the population brought about by the fall in the number of births compared   to the number of deaths is the phenomenon of demographic decline. What are its causes and consequences? How to explain why the fertility rate is changing, what factors contribute to the birth rate falling or rising, how to understand the connection between the birth rate and the number of women of childbearing age and their fertility? Finally, how will these factors evolve in the future?