This article explains how to connect to a server on Discord using a computer.
Steps
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Step 1. Copy the invitation URL to the server
To join a server on Discord, you need to have an invite link. If you don't know who can invite you, visit https://www.discordlist.net, select the full invitation link next to the server you want to join, then press Ctrl + C (Windows) or ⌘ Cmd + C (macOS).
Invitation links begin with
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Step 2. Visit https://www.discordapp.com using a browser
If you are not already logged in, log in now.
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Step 3. Click on +
This button is located in the left column at the top of the screen.
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Step 4. Click Add a Server
It's a green button.
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Step 5. Paste the invitation link in the indicated field
Click on the empty box, then press the Ctrl + V (Windows) or ⌘ Cmd + V (macOS) keys to paste the link.
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Step 6. Click Join
This green button is located in the lower right corner of the white window. At this point you will have connected to the server.