Traditional Chinese characters
Traditional Chinese characters is one of the two commonly used forms of Chinese characters. As its name shows, it is the "traditional" written form of the Chinese language that has first come about during the Han Dynasty (shortly after the Qin Dynasty) in 206 BC. The name "traditional" is used to set them apart from simplified Chinese characters.
Court officials in the Han Dynasty believed that Xiaozhuang characters, which were standardized under Emperor Qin Shi Huangdi with the unification of China, were hard and used too much time to write, since Chinese characters at the time were written using curved lines instead of more angular lines. So Han officials decided to simplify writing Chinese characters by using multiple strokes, or lines, to form characters and radicals, rather than long curved lines. The changed Xiaozhuang characters is now commonly known as Hanzi (Simplified Chinese: 汉字 / Traditional Chinese: 漢字, meaning "Han characters"), because they were from the Han Dynasty. They became the standard writing system of Chinese and were also used (with some differences) in Japanese, Korean, and Vietnamese, although only Japanese still uses them to this day.
These older, "traditional" forms of Chinese characters would remain more or less the same, although there were a few changes now and then, until the People's Republic of China (PRC) was formed in 1949. At that time, the Communist Party of China (CPC) started to create simplified Chinese characters, in which anywhere between 20-30% of all the Chinese characters used in daily life were replaced by ones with less strokes and easier to write. This move by the CPC, which took place in the 1950's throughout Mainland China, was made in order to make education more available to common people, especially farmers.
At the same time, the government of the Republic of China, which had fled to Taiwan, chose not to simplify its writing system and so they continue to use traditional Chinese characters. The Cantonese-speaking territories of Hong Kong and Macau have also kept using traditional characters, even though they are politically part of the PRC which uses simplified characters. The Chinese taught as a second language in Southeast Asia uses simplified characters, and the government of Singapore and the Chinese community in Malaysia have adopted simplified characters as their standard script. Many immigrant communities of overseas Chinese also tend to use traditional rather than simplified characters.