BookTok influences what you read, even if you aren't on social media

Romance novel The Hating Game was published 10 years ago, before online bookish communities were as massive as they are now.

Back then, Sally Thorne's debut novel became popular through word of mouth.

"The word of mouth that originally sold my book is now social media recommendations, which seem to hold just as much weight," the Canberra-based author says.

If you're looking for a new book to read, you may ask family or friends for a recommendation, but it's increasingly likely that you use social media.

According to the Understanding Australia Reads survey, about 80 per cent of Australians read a book at least once a year; of those readers, 8 per cent searched for books through book-related social media.

It's a hashtag on TikTok that now has more than 85 million videos contributed by an international community.

But many of the biggest creators and books featured in videos are from the US and the United Kingdom.

"I would say of my book sales, 1 per cent would be Australia and 90 to 95 per cent would be the US and the rest would be the UK," Thorne says.

BookTok is only the latest addition to online book sub-communities, with the original platforms Bookstagram (Instagram) and BookTube (YouTube) dating back more than 10 years.

These social videos are often spoken about as a form of word of mouth, but is that really the case?

Marc Cheong, a senior lecturer at the University of Melbourne, says they're unlike other recommendation methods.

When you have a book recommendation from a friend or book club that you may not have liked, you aren't bombarded with recommendations for similar titles.

"There's no central intermediary that says, 'Hang on a second, you might like to read this one,'" Dr Cheong says.

According to Dr Cheong, the word "algorithm" has become shorthand for how social media companies use our data to craft the feeds we see.