How did the Norman attack go?

In the 9-11th century, the northern regions of Europe suffered greatly from the constant raider raids of the Normans. It is known that the Normans or Varangians lived on the territory of the Scandinavian Peninsula and on the territory of Denmark, from where they went on campaigns on their ships. The whole essence of the tactics of the Normans boiled down to an unexpected and quick attack. They landed and plundered a nearby city, and then also quickly went back to their Drakars with the prey they had collected.