Electricity is the term given to the set of phenomenon related to existence and movement of charged particles. The fundamental of electricity itself lies in charges, that can either be positive or negative. However, the type of charge itself depends on the presence of negatively charged subatomic entities (particles) called electrons, the absence of electrons depicting positive charge.

Yosemite falls is a waterfall in Yosemite National Park, Yosemite, California. It is one of the most visited site in the park as of 2022.It is the tallest waterfall in whole of North America. Yosemite Falls in California, USA. History President Abraham Lincoln first authorized some protection for Yosemite in 1864 (at the height of the Civil War). The establishment of the national park 26 years later offered broader protection for a much larger area and also provided a template for the very idea of a national park system.In 1894, the USA declared this one of it's first national park.

Lung Tumour is the abnormal growth of lung tissues that can significantly block the airways in the lung and can cause issues in breathing.  History “Lung cancer continues to be the leading cause of death in both men and women in the US, with over 158,900 deaths in 1999. Worldwide, lung cancer kills over 1 million people a year. Extensive prospective epidemiologic data clearly establish cigarette smoking as the major cause of lung cancer. It is estimated that about 90% of male lung cancer deaths and 75–80% of lung cancer deaths in the US are caused by smoking each year” (Hecht, 1999). Clearly, lung cancer is an important and widespread disease that constitutes a major public health problem. This was not always so. Some 150 years ago, it was an extremely rare disease. In 1878, malignant lung tumors represented only 1% of all cancers seen at autopsy in the Institute of Pathology of the University of Dresden in Germany. By 1918, the percentage had risen to almost 10% and by 1927 to more th

Epithelium, also known as ' Epithelial tissue' is one of the four basic types of animal tissues, the other four being connective tissue, muscle tissue and nerve tissue.

Conjunctivitis is an infection on the topmost layer of the eyes. The infection generally results in reddening of the infected eye and is contagious. History