A Singaporean friend of mine calls his Chinese: 华文. I didn't realise that this also meant Chinese.
What is the difference between 华文 and 汉语?
It should be 华语. May be it is a Singapore thing to use the term 华文.
华 or 华夏 is the origin of Chinese culture. While 汉 is one of the greatest and longest ruling dynasty in Chinese history. The words 华 and 汉 along with 唐 (another great dynasty) are commonly used as representative of "Chinese"
华语, 汉语 and 唐話 (Cantonese) all mean "Chinese spoken language" (中国语)
Both 汉文/ 汉字 and 唐字 (Cantonese) mean "Chinese written language" (中文/中国字)
Both 华人 and 唐人(Cantonese) mean "Chinese people" (中国人)
All of the following names mean the Chinese languages (including variants and dialects):
All these four names mean the same, except 语 (語) is more likely to refer to spoken languages, while 文 is more likely to refer to written languages.
The terms 汉语 and 中文 are more likely to be used in China, while the terms 华语 and 华文 are more likely to be used in South East Asia.
The meaning of 中华 (中華), 华夏 (華夏), 华 (華), 汉 (漢) are similar, so they are often used interchangeablely.
The character 夏 (Xia), which means summer in modern Chinese, is a dynasty name in early peroid of China's history, and the character 華/华 means splendid, grandeur, luxury, etc, in ancient China, so the Xia dynasty claimed to be 华夏/華夏 (Hua Xia), which means Splendid/Grandeur Xia.
There are also two far-reaching dynasties in Chinese history, 漢/汉 (Han) dynasty and 唐 (Tang) dynasty, the Han people is the largest ethnic group in China now. 漢語/汉语 became the official name of Chinese language, and 唐人 is also an alias of Chinese people since Tang dynasty.
There are many variant names for Chinese language and Chinese people nowadays, for example 中華/中华, and 華夏/华夏 also are used for China sometimes, 漢語/汉语 and 華語/华语 are used for Chinese (language) sometimes, and 唐人 and 華人/华人 are used for Chinese (people) sometimes.
These names are from different dynasties and are still in use today in different occasions.
漢語/汉语: Official name for Chinese language.
國語/国语: Mandarin, official spoken Chinese standard. The name is still used in Taiwan & HK.
普通話/普通话: Mandarin, the name was introduced in mainland China, called 国语 formerly.
中文: A modern word, seems to replace 漢語/汉语.
唐人: Used outside of the Greater China area, especially Europe and America.
華人/华人: Used outside of the Greater China area, especially certain parts of southeast Asia.
華文/华文: Used outside of the Greater China area, especially certain parts of southeast Asia.