An alternative name for Western dragons is wyrm, a word clearly related to "worm". This name is more commonly used for serpentine, water dwelling dragons but can be used for any of them. Wyrms are to be especially common in Britain.
Outside of Britain, most Western dragons live in caves or mountains or hidden away in the forests. They often guard a stash of gold. Western dragons are often used to symbolise greed.
Dragons vary as much as people do. Although many Western dragons are brutal, ignorant creatures who kill and eat humans others are ancient, wise creatures more akin to those found in the East.
The dragons of China and Japan are almost exclusively benevolent mythological creatures. In fact they are so different in nature from Western Dragons that it may be more reasonable to consider them as dissimilar creatures, rather than as the same creature interpreted differently.