Welcome again everybody, from your favorite matrix server overlord friendly matrix server admin! Make yourself at home. In the time-honoured tradition of our group, here is our weekly discussion thread.
Type ":" and the first few letters and you should see a selection pop up. You can also find it in the "*" category in the emoji picker located above post/comment text areas.
Emojis on lemmy are just markdown links to images, you can use them by typing ![]( <image file> "emoji <name of the emoji>") copy-pasting an image in the text editor should automatically generate the link, you would just have to add what is between quotation marks.
Emojis remove the need to upload multiple images to the server, save you a trip to your image folder, and can easily be used inline as if they are part of a sentence. They also give instances their own flavor.