I'm new to ubuntu, and I'm still trying to learn linux. So i had this idea to start a little project. When my friends come over, and they connect to my wifi, my linux computer would automatically send them a message saying something like "Welcome to my home" as soon as they connected. I was trying to impress my friends, but the main goal is to actually learn linux better. Problem is, I have no idea where to start. Any help on learning or how to start it would greatly be appreciated.
What app do you want them to receive your message in? Well, let's assume it's a web browser. So, when they ask for their first web page, you instead redirect them to your digital welcome mat; they see it, click continue, and then go to their original destination.
This, however, is not a function of a desktop or laptop machine, this is a server function where you create a Directory Naming Service server for your home network. Every web request they make goes through DNS (which means that machine must always be on for anyone to use the Internet from your place), and you would need to write custom code for it so their first request is held until they've seen the digital welcome mat.