Follow-up messages allow you to send multiple messages from a single interaction. Example****
Follow-up messages and interaction responses work with a unique interaction token which is generated when an interaction is created. This unique token is only valid for 15 minutes. Then, interaction response/follow-up messages sent after that won't be successful.
Ephemeral Responses
Using flags we can create ephemeral (private) responses. Example****
This will only respond to the author of the interaction, find the Docs here
Reactions
With Shandler's newest update we can now react to messages. Example****
Attachments
Using Discord.js MessageAttachments, we are able to send attachments in our interactions. Example****
Embeds
Using Discord.js MessageEmbeds, we are able to send embeds in our interactions. Example****
let m = await interaction.reply("Bello");
let i = await m.reply("This is a follow-up message");
i.reply("This is another follow-up message").then(console.log);