Discord allows you to post messages from other websites and apps using Webhooks which is really useful, in the past I’ve used it from IFTTT and also linked into google calendar to share messages between them. What do you do if you want to get a webhook to ping roles or users at the same time it posts a message?
Well you need to use a special syntax to mention channels/users/roles etc in a webhook. For channels and users you should be able to use <@CHANNELID> and <@USERID>. To grab the IDs you need to go to settings->advanced then turn on developer mode. Once you have done that just right click a user or channel and hit “Copy ID”. Just paste it with the above so it looks something like <@684309756589074816>.
For roles its a similar approach to the above but you need to use <@&ROLEID> to get it working. You can also use it for other things like emojis if you need to for any reason! It took me a while to work it out so thought I would post here and I hope this helps someone.