What does "loading" mean?

learn to use element-ui, to see the lock modifier in the loading component, and then explain the document as follows:

clipboard.png

but I still don"t know what it means.
lock means to lock. Does it mean to lock the current area and display the load bar in the current area?
what"s the difference between it and the modifier fullscreen,body?
Baidu has not found an explanation either. I hope those who know it can answer it. Thank you

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Apr.02,2021

when you first set lock to true, to dynamically add data, before the request is successful, there will be a loading sign, the request is successful, the data will be displayed, and the lock value will be locked and loaded by false,. Do not know this explanation, can you understand


lock is the locking screen. If you add this, you can't scroll if the screen has a scroll bar

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