in a lamp having wick and oil what causes to continue to burn when it is lighted up?

is it vapourisation or evaporation

When you light a lamp, you notice a stream of white smoke leaving the wick. This stream is oil vapor that has condensed into a visible form. It continues to form as long as the wick is hot enough to vaporize oil.
The reason the wick does not burn is because the vaporizing oil cools the exposed wick and protects it.