What's the meaning of these two lines please

Hi,
I am testing an ESP32CAM + TFT code, there are two lines as:

AsyncWebServer webserver(80);
AsyncWebSocket ws("/ws");

What's exactly that mean?

And what's the meaning and different of:

websocketsserver;
asynchronous;
namespace websockets;

Some code used 'websocketsserver;', some other code used 'asynchronous;', it that necessary or just the Author's favourite?
Thanks
Adam

https://en.cppreference.com/w/cpp/language/direct_initialization
https://www.learncpp.com/cpp-tutorial/variable-assignment-and-initialization/

Those names are meaningless without context.

Thanks.