The type of Chinese sailing boat called a 'junk' derives its name from the Portugese 'junco' which came from the Malay 'jong', which is thought to come from the Javanese 'djong'.
The word 'junk' in this sense has been used in English since at least the fourteenth century and probably earlier.
The junk boats were sailed around the coastlines of China.
If you trace the origins of the word you will find it comes from words meaning "boat". So, it doesn't really add much meaning. Of course, it's only used for a particular sort of boat, particularly the Chinese junk.
You're probably referring to the boats commonly seen trolling the waters of Victoria/Hong Kong Harbor and that are likewise commonly seen in movies filmed in Hong Kong. They are called "junks or "junk boats". The term "junk" is a derivative of the Portuguese word "junco".
Chinese junk boats are primarily used for trading and transporting exports and imports. In the past, they also have been used for military combat.
They are all boats.
Spam or junk.
War boats were called triremes.
The viking boats were called tall ships
The small boats of Venice are called gondolas.
yes
life boats
the boats look a little like a canoe and are called kayaks