As described in the Wikipedia article, a chip pan is a pan that contains oil for frying. The oil is heated to a high temperature, and then usually a metal basket is lowered into the pan for frying of things, such as chips.
The article contains this sentence:
Chip pans are commonly used in the United Kingdom and Republic of Ireland, although are slowly being outmoded by deep fryers.
When I look up the article for deep fryer on Wikipedia, it described what seems to me to be the same thing:
Deep fryers generally have a basket to lower the food into the oil tank and raise it when the food has finished cooking.
These descriptions appear to be the same to me, are there any differences between the two that I don't understand?