Where an announcements channel might not get the job done, Discord has a pin messages function that'll allow you to have quick access to important messages from way far back or as recently as you like.
Or the most dangerous veggie to have on a boat.
Ladies and Gentlemen, ready your thumbtacks:
To pin a message, just click on the edit message cog at the far right of the chat window:
If your role has the manage messages permission (or you're the server owner), you'll see the "pin" feature in the drop-down menu.
Right-clicking on the message will also work:
Clicking the "Pin" option will save that message to the pin window:
As the prompt says, make sure you double check for posterity and greatness. These aren't just any common messages, you know.
Collapsable Corkboard, Endless Time Warp:
Any pinned message will appear in the pin window, accessed by clicking the pin icon in the top-right corner:
Another important point is that no matter how long ago the pinned message is, you can click the "jump" link next to the pinned message in the pin window to jump all the way back to when that message was originally written:
When you're ready to unpin a message, just click the "X" icon next to that "Jump" button we saw earlier:
Last Protip: By holding shift and clicking the "X" unpin icon in the pin window, you can bypass the above "kthx" unpinning message to unlock true rapid-fire unpinning madness.