I've figured out how to attach images on a post, but is there any site which will allow me to make diagrams online? I've tried draw.io, and it does a great job, but to a certain extent. I've tried geogebra.org, but the links created by GeoGebra for the image are to big to be handled by my clipboard. If I try to download the image, it gets downloaded in a random format which my laptop can't handle. Any way other than installing software? I use a MacBook, so any application on the AppStore would do too. If the only way is to install software, is there any reliable software and link which can do everything I need it to? Comment what you use.