According to different purposes and locations, there are different classification methods, such as location: one is to walk outside the mother spacecraft, such as the International Space Station or the Space Shuttle, which is a form, and the other is to walk on the surface of the moon and then walk on the surface of Mars. Secondly, according to the plan of spacewalk, there are emergency ways to classify: one is called planned spacewalk, the other is called temporary increase without plan, and the third is called emergency spacewalk, which suddenly appears problems and carries out spacewalk. According to the tasks, there are verification spacewalk, assembly spacewalk, maintenance spacewalk and payload spacewalk. For example, the first spacewalk between the United States and the Soviet Union was a confirmatory spacewalk, depending on how well the technology was mastered; The assembly class is to assemble the space station; There is also maintenance, which is the maintenance of spacecraft; Payload spacewalk is to do some experiments, including installing some test equipment on the surface of the moon. There is also a classification method, which is based on life support system. Which method is used? One is called umbilical cord, just like the umbilical cord of a baby. Umbilical cord plays two roles. One is that the life support system inside is delivered to astronauts through this umbilical cord, including oxygen removal, including carbon dioxide, including temperature control, including power supply and communication. The second function is to play the role of safety rope, but it is not used now. At present, most of them adopt the "autonomous" type, that is, carrying the life support system on the astronauts' backs like backpacks. Of course, sometimes it seems that astronauts still have ropes outside the cabin. It is not an umbilical cord, but a safety belt. Hang two ropes and a hook around your waist to prevent the astronauts from drifting away. In addition, they are fixed in one place, which can make them work better. So there are many kinds of classification methods.