Samsung (Hangul: 삼성; hanja: 三星; Korean pronunciation: [sʰamsʰʌŋ]) is a South Korean multinational conglomerate company headquartered in Samsung Town, Seoul. It comprises numerous subsidiaries and affiliated businesses, most of them united under the Samsung brand, and is the largest South Korean chaebol (business conglomerate).Samsung was founded by Lee Byung-chul in 1938 as a trading company. Over the next three decades, the group diversified into areas including food processing, textiles, insurance, securities and retail. Samsung entered the electronics industry in the late 1960s and the construction and shipbuilding industries in the mid-1970s; these areas would drive its subsequent growth. Following Lee's death in 1987, Samsung was separated into four business groups – Samsung Group, Shinsegae Group, CJ Group and Hansol Group. Since 1990s, Samsung has increasingly globalized its activities, and electronics, particularly mobile phones and semiconductors, have become its most important source of income.Notable Samsung industrial subsidiaries include Samsung Electronics (the world's largest information technology company measured by 2012 revenues, and 4th in market value), Samsung Heavy Industries (the world's 2nd-largest shipbuilder measured by 2010 revenues), and Samsung Engineering and Samsung C&T (respectively the world's 13th and 36th-largest construction companies). Other notable subsidiaries include Samsung Life Insurance (the world's 14th-largest life insurance company), Samsung Everland (operator of Everland Resort, the oldest theme park in South Korea), Samsung Techwin (an aerospace, surveillance and defense company) and Cheil Worldwide (the world's 15th-largest advertising agency measured by 2012 revenues).Samsung has a powerful influence on South Korea's economic development, politics, media and culture, and has been a major driving force behind the "Miracle on the Han River". Its affiliate companies produce around a fifth of South Korea's total exports. Samsung's revenue was equal to 17% of South Korea's $1,082 billion GDP.In 2013, Samsung began construction on building the world's largest mobile phone factory in the Thai Nguyen province of Vietnam. Samsung has been able to achieve the largest market share of nearly 31% in the global smartphone segment, as of 2013.