Why in the code below, node declared as datatype?

Question

I learning data structures that provide by community in this app. When I learning about Linked List and see the code example in C++, I really confused because I only know basic programming. At this part, I really2 don't get why node declared as data type. Thanks for the help and sorry for my poor english
https://code.sololearn.com/cW7MvH6278Bx/?ref=app
https://code.sololearn.com/cW7MvH6278Bx/?ref=app

Answer 1

Because you are creating a pointer of node type

Answer 2

Because you introduced class `node` at line 4. A class is a user defined type.