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For those new to AO3
Authors can see your bookmarks as a default. You have to mark them as private if you don't want authors to see them. There is an argument that bookmarks are a reader's space, but if you don't want authors to see what you are saying, make the bookmark private.
There is no algorithm on AO3. Seriously. It does not exist. Sorting by kudos, comments, length, etc. is the closest thing you will get. It is very much a curate your experience situation. Embrace it because you never know what gems you'll find if you give less popular fics a chance.
Depending on who you ask, kudos are not a good metric to judge a fic on anymore. As to if they ever were is, again, depending on who you ask. There is a spider/web crawler (we call it the kudos bot) who gives a bunch of guest kudos to fics. We cannot summon it and we cannot remove the kudos. At best, we can set our fics to private. So, if you see a fic with way more kudos than views, that's why. Many of us do not want these kudos, but we have to live with them.
Concrit (constructive criticism) is divisive because this is a hobby for many people. There is a culture on AO3 for concrit to be opt-in instead of opt-out, but not everyone subscribes to that. If you do not see an author's note saying concrit is OK, you can ask if it's OK. If they don't say anything, take it as a 'no'. If the author is cool with concrit, great. Concrit away.
Asking for updates is also divisive. Some people want/need that encouragement and some don't. Leaving a polite 'can't wait for the next chapter' is totally fine. If you ask for an update and the author asks you not to, please respect their wishes. You don't know what else is going on behind that screen. We all use fic for our own reasons and it's impossible to tell if that was someone's project to forget about things that they don't want to deal with.
There is a difference between A/B and A&B. A/B is for shipping and A&B is for non-shipping relationships (such as platonic and familial relationships or bullying or work situations). Please tag accordingly and please do not accuse people of writing shippy fic when they tagged it A&B.
Comment totals on AO3 count author responses. It doesn't make a distinction between a response and a new comment thread. Comment thread counts are in the author's stats page only available to them. Authors are not inflating their comment counts by responding to get more views. They are just trying to interact with people who support them.
Not all authors respond to comments. For many older fans, this can be due to years of harassment in fandom, witnessing friends being harassed, not having time, etc. etc. Their reasons are their own and it does not mean you are a bad person or said something wrong if they don't respond to you nor does it say anything about them. Authors do not owe you interaction just as you do not owe them comments. It's your prerogative if you only want to leave comments on fics where the author answers back, but it does not mean the author isn't grateful or doesn't care. You do not know what else is going on.
You cannot take a kudos back. Seriously. It's permanent. If that means you want to wait until a fic is finished to leave a kudos, that's totally fine. To authors, if you see a bunch of comments and views, but few kudos, this is probably the reason. It does not mean your fic is bad; it just means readers are holding kudos back until the fic is finished, which is perfectly legitimate.
Please read author's notes at the beginning and end of chapter updates. This is where authors are The Most Likely to tell you if there has been a change in their update schedule, if they made changes to previous chapters, explained a certain choice they made, etc. Same with checking the tags thoroughly before reading a fic. Most authors take tagging and warning/updating readers very seriously and the spaces they can do it in are the author's notes and the tags.
Because there are so many people from so many cultures on AO3, the categorizing of fics may not be totally even across the board. Tagging might have discrepancies. For instance: some people might view smut as M and not E depending on the level of detail; some might even view it as T. Please exercise caution and look at tags carefully when clicking on a fic. If you come across something you do not like, the back button is always an option.
There is a hard limit of 75 tags on fics, so not all characters that appear in a fic are likely to be tagged. For many of us, we only tag major players, major ships/&-relationships, and background relationships as a courtesy and save the rest of our tags for known triggers and making it easier for people to find our fics by tagging the tropes we use and certain parts of the content (such as 'AU where A loses their voice').
If you hate a character or a ship or a certain trope or have certain triggers, there is nothing wrong with asking a fandom friend for recommendations. If anything, we probably should bring back fic rec lists and you could be doing an amazing service for fandom if you start making one based on your preferences. Don't rely purely on other platforms to lead you to amazing fics; you never know how that person is finding fics and they could be missing out on some really amazing ones.
AO3 currently does not have a messaging system and many users prefer it that way. I am not positive what the future holds, but if any author wants you to get in contact, they will probably leave other socials in their notes or on their profile. They might even tell you to contact them in a comment response. You can absolutely respond to them on other social media platforms and talk fics or art or fandom. The AO3 lack of messaging is a comfort for many people because of previous experiences regarding harassment and, for some, that's the closest thing to a social media that they have. Some fandoms are more than 40 years old and not all of it has been positive for everyone.
Please do not leave 'placeholder' ideas in the fic tags. By this I mean, 'here's an idea I plan to write. Let me know if you like it!' and there's one or two sentences but no actual fic. AO3 is not social media. You can be reported for this and the post taken down as per AO3's guidelines. Fic, meta, and art are welcome on AO3. A plan to write a fic is not.
Lastly, please enjoy your time on AO3. It is an archive that dedicates itself to preserving fandom works, whether we agree with those works or not.
In response to the articles I've seen suggesting that the Power of Love should be retired as a trope
Writers, be honest, why do you post fanfic?
I am seeking validation through comments/kudos/hits
I wrote the thing and now want to make everyone else's problem
My friends urged me to do so
I'm trying to make fandom friends via the comment section
I am seeking to become a published writer some day and want the feedback
I wrote it for me first, but I post in case someone else might like it
Other (please comment in comfortable)
What live-action Netflix show will you forever be pissed was cancelled?
Gentefied
The Get Down
The OA
First Kill
Sense8
Julie and the Phantoms
One Day at a Time
Glow
Anne with an E
Warrior Nun
Which of my favorite pieces of media is also your favorite?
Fullmetal Alchemist (manga and Brotherhood)
Katanagatari
Princess Tutu
Derry Girls
Bridgerton
Coundown by Beyonce (especially that music video)
Skyworld album by Two Steps From Hell
Inkheart by Cornelia Funke
The Princess Bride
The Dark Crystal (movie and Age of Resistance)
The main difference between 'Fuck this show (derogatory)' and 'FUCK THIS SHOW (lovingly)' is that the first one is really rooted in 'I am finished with this show's bullshit' while the second is 'I expected happy-fun times and instead I'm feeling things and am being forced to confront things I'm not ready to as I sob while eating ice cream'
Which of my favorite things is also your favorite?
Simple and Clean by Utada Hikaru
Monster by Urasawa Naoki
Neko Atsume
Artemis Fowl (we don't talk about the movie)
Kiki's Delivery Service
Disney's The Little Mermaid
Kill this Love by Blackpink
Masayume Chasing by BoA
Something Happened on the Way to Heaven by Phil Collins
Stardust