Please, I need to learn network programming by lazarus specially by indy.
Is there any course or tutorials to learn It.
Not specifically for Indy. Well, I mean, there used to be an
"Indy in Depth" eBook, but I don't know if it's still available. And, there used to be demos available, but I think they got lost to time as well.
The
online documentation does include an example in its "Introduction to Indy" section.
Indy is mainly a comprehensive library of classes/components on top of plain TCP sockets, so most general networking/TCP tutorials should be adaptable to use Indy classes. If you have specific questions, you can ask them in this forum, or
anywhere else I provide Indy support.
Just sit tight, sooner or later @Remy Lebeau, will see it and respond -- He's the maintainer of Indy 
Or, when I'm summoned...
