What is Eaglercraft?
You can watch SalC1's video on it, who explains everything clearly
Why people like Eaglercraft
Eaglercraft has exploded in popularity thanks to its being able to bring the real Minecraft Java experience inside of a fifteen-megabyte HTML file. Majority of the people who play Eaglercraft want private servers for their friends that run 24/7, however used to not be possible without paying a single cent or running it on your PC 24/7. Well it is now possible to run it 24/7 for completely free and not needing to host it on your PC.
How you can host it for completely free without running it on your PC
Step 1: Go to eagler.host
Step 2: Make an account
Step 3: Click create server and then fill out all the details for your server
Step 4: Run your server and you have a free 24/7 server (IF YOU WANT TO SUPPORT ANY VERSION OF JAVA; Use ViaVersion, ViaRewind and ViaBackwards)
The Drawbacks
Every free host has its drawbacks, and this one is no exception. If you plan to run a server with more than 5–10 players, you should consider a paid host since this one only provides 2 GB of RAM. They will be adding credits soon, but for now that’s my recommendation. Keep in mind that storage is also limited.