- Chinese Communist Party (Wikipedia)
The Chinese Communist Party (CCP), officially the Communist Party of China (CPC), is the founding and sole ruling party of the People’s Republic of China (PRC). Under the leadership of Mao Zedong, the CCP emerged victorious in the Chinese Civil War against the Kuomintang. In 1949, Mao proclaimed the establishment of the People’s Republic of China. Since then, the CCP has governed China and has had sole control over the People’s Liberation Army (PLA). Successive leaders of the CCP have added their own theories to the party’s constitution, which outlines the party’s ideology, collectively referred to as socialism with Chinese characteristics. As of 2023, the CCP has more than 98 million members, making it the second largest political party by membership in the world after India’s Bharatiya Janata Party.
- Klein bottle (Wikipedia)
In mathematics, the Klein bottle (/ˈklaɪn/) is an example of a non-orientable surface; that is, informally, a one-sided surface which, if traveled upon, could be followed back to the point of origin while flipping the traveler upside down. More formally, the Klein bottle is a two-dimensional manifold on which one cannot define a normal vector at each point that varies continuously over the whole manifold. Other related non-orientable surfaces include the Möbius strip and the real projective plane. While a Möbius strip is a surface with a boundary, a Klein bottle has no boundary. For comparison, a sphere is an orientable surface with no boundary.