Discussion
So that students can connect with classmates via platforms on which they're already spending (too much!) time, CS50 has official communities on Discord, Ed, Facebook, Gitter, Instagram, LinkedIn, reddit, Slack, Snapchat, Stack Exchange, and Twitter. If not already a user of any of those, allow us to suggest that you start with reddit!
Discord
Prefer to interact with classmates via Discord? Visit discord.gg/QYZQfZ6 and join CS50's Discord server!
You can say hello to David at @malan.
Ed
Prefer to interact with classmates via Ed? First create a free Github account (if you don't already have one!) and then visit cs50.harvard.edu/ai/ed to join CS50W's Ed discussion forum!
Prefer to interact with classmates via Facebook? Visit facebook.com/groups/cs50 and join CS50's Facebook group!
You can follow CS50 itself at facebook.com/cs50, Brian at facebook.com/BrianYu28, or David at facebook.com/dmalan.
Gitter
Prefer to interact with classmates via Gitter? Visit gitter.im/cs50/x and join CS50's Gitter channel!
Prefer to interact with classmates via Instagram?
You can follow CS50 itself at instagram.com/cs50 and David at instagram.com/davidjmalan!
Prefer to interact with classmates via LinkedIn? Visit linkedin.com/groups/CS50-7437240 and join CS50's LinkedIn group!
You can follow Brian at linkedin.com/in/brian-yu or David at linkedin.com/in/malan.
Prefer to discuss CS50 with classmates via reddit? Visit CS50's "subreddit" (aka /r/cs50) at reddit.com/r/cs50. You're welcome to browse and search for answers without a reddit account. But if you'd like to ask questions or upvote or downvote posts, you'll want to create a reddit account and log in at ssl.reddit.com/login, then return to reddit.com/r/cs50. That account will be distinct from your edX account, but you're welcome to (try to!) choose the same username.
Be sure to read up on "reddiquette" at reddit.com/wiki/reddiquette so that you don't get downvoted! And you might want to install Reddit Enhancement Suite in your browser, which adds a lot of nice features to reddit.
If inclined to post code that you've written,
- keep in mind the course's policy on academic honesty,
- paste the code into a "gist" at gist.github.com and then post that gist's URL rather than posting the code itself (so that it's nice and readable).
If you'd like to post a screenshot that you've taken, simply upload it to imgur.com and then paste that upload's URL into the text of your post, per reddit's FAQs.
Finish one of CS50's courses already? Like to field questions on CS50's subreddit as an alum (i.e., graduate) of CS50? Let us know your reddit username at cs50.edx.org/alum so that we can give you some "flair" so that "alum" appears next to your name when you answer questions, so that students know you're there to help!
Slack
Prefer to chat with classmates from around the world in real-time at cs50x.slack.com? Request an invitation at cs50.edx.org/slack, and we'll follow up via email! Download native apps for Android, iOS, Mac OS, and Windows at slack.com/downloads.
You can say hello to David at @malan.
Snapchat
Prefer to interact with classmates via Snapchat?
You can follow CS50 itself at snapchat.com/add/cs50!
Stack Exchange
Prefer to ask a question of classmates via CS50's "Stack Exchange" at cs50.stackexchange.com? Sign up at cs50.stackexchange.com/users/signup. Be sure to take the 2-minute tour so that your questions don't get downvoted! You're welcome to browse and search for answers without a Stack Exchange account too!
If inclined to post code that you've written,
- keep in mind the course's policy on academic honesty, and
- paste or type the code as preformatted text.
Prefer to interact with classmates via Twitter? Simply tweet with hashtag #cs50.
You can follow CS50 itself via @cs50, Brian via @brianyu28, or David via @davidjmalan.