What does it mean to say that a person is an "operator"?

On the one hand, an "old slick" refers to a person who has stayed in a forum for a long time, knows the situation of this forum very well and has extensive diplomatic relations and so on. On the other hand, it means that you are more proficient in the world and have more experience in handling things. In addition, it also refers to the food "fried dough sticks". Fried dough sticks are a kind of long and hollow fried pasta with crisp and tough taste, which is one of the traditional breakfasts in China. In Guangdong and Fujian, it is also called fried ghost or fried noodles, in Chaoshan and other places, it is also called fried fruit, and in the north, it is also called fruit.