A silo, or web content hosting silo, in the context of the IndieWeb, is a centralized web site typically owned by a for-profit corporation that stakes some claim to content contributed to it and restricts access in some way (has walls).
Silos are characterized by the following:
- require you to create an account specific to that site to use it (silo identity)
- allow you to interact on the site only with others with accounts on the site (silo contacts / social network)
- allows you to post some type of content (text, hypertext, images, video)
- and typically one or more of the following:
- an access wall that prevents indexing of (at least some of the) content you contribute
- a restrictive terms of service (TOS)
- claims some ownership or license to any content you create within the silo
- restricts your ability to import/export your content, or content about your content (e.g. comments, tags)
In contrast, see: commons.
What are the silos? Control. The silos are computer-generated dream worlds built to keep us under control in order to change a human being into this. 
[holds up chart showing clicks on ad units]
(with apologies to )
For a brief history of the rise and fall of various silos, see the History page for launch, acquisition, death, and zombification years/dates. See site-deaths for upcoming and past silo deaths in particular.
These silos are both popular, and used by a number of indiewebcamp community members (often via POSSE) to stay in touch with their friends.
If you have friends that are active on a popular silo, feel free to add it to this list.
New And Hip Silos
There's always new silos being launched, some of which gain some amount of traction with early adopter crowds. Here are a few
Add any silo to this list that you're an active user of and especially if you can document how to export data from it.
A few silos have given users tremendous flexibility in the look and feel of their experience and the content they post.
- Blogger - quite a bit of control via templates
- Tumblr - also lots of control via templates
- WordPress.com - some choice of free templates, and more choices as a paid option
Historically (but no longer)
- MySpace (~2002-2009?) - so much control over the HTML and CSS of your profile page that many compared it to GeoCities, and not in a flattering way.
Silos have innovated UX since 2003 far more than the blogging/RSS/Atom "communities" (as much as there was such a thing).
Here are some examples of UX innovations that silos either created, popularized, or refined to be much more usable, in rough temporal order.
- favorites - Flickr (2004)
- Integrated reading/creating UI - LiveJournal, Delicious (2004), Tumblr, Twitter (2006), Facebook (2006? when did Facebook launch their Newsfeed?)
- checkins - Dodgeball (2005), Foursquare (2009?), copied by Facebook (2010?)
- scrobbles - Last.fm (2000-2005? what year exactly?)
- block - Flickr (2005-07-27 per , before that they had an ignore feature (superseded by block) which sounds like a harsher form of mute)
- likes - introduced by FriendFeed 2007-10-03, then copied soon after by Facebook which quickly popularized them.
- reply-context - Twitter (20??-??-??). It was a small but important incremental step to go from reply posts on their own pages (see "User Innovation Inside Silos" below) to displaying the context of what those reply posts (tweets) were in reply to.
- recursive reply-contexts - Twitter. Another incremental if obvious step, Twitter started displaying the reply contexts of reply contexts themselves, all the way on up to an original tweet.
- Aaron Swartz invented this first - example
- legacy contact - Facebook (introduced 2015-02-12)
- ... add more and attribute the innovating silo
User Innovations Inside
Despite silos typically exerting tight control over their look, feel, and overall user experience, users have found ways of innovating inside silos, which silos have often adopted and integrated into their UX.
- reply permalinks - Twitter - reply posts on their own permalinks instead of just fragment links on a post.
- Specifically, @-replies, were previously "only" in comments (e.g. comments in MySpace and Flickr used @-name conventions to indicate who they were responding to in a thread). When Twitter users started using @-reply syntax in tweets to intentionally direct their tweets at particular people, Twitter adopted this in multiple ways:
- auto-link @-mentions to profile pages (was in response to user-behavior)
- show @-reply tweets only to those who followed both the replier and the user being replied to.
- auto-fill "Reply" textarea underneath a tweet with @-mention of the tweet author
- auto-fill "Reply" textarea also with @-mentions of anyone else mentioned in the tweet.
- hashtags - as proposed by Chris Messina on Twitter, then adopted by users, then eventually auto-linked by Twitter to search results for mentions of that hashtag.
- retweets - the "RT @-name:" syntax (originally ReTweet:) was purely a user innovation to indicate that they were passing along text/content from another user. Twitter both:
- codified "RT" into a one-click button (so easy to use as to cause million+ retweeted posts)
- showed the original author of the tweet, when presenting the retweet in others' reading views.
- 🍞 for like - Ello users in Germany adopted a convention of typing ":bread:" to generate a bread emoji (🍞) in a comment as a simple indicator of "liking" a post, since Ello lacks an explicit like/favorite feature.
- ... add more user innovation inside silos with attribution to user(s) if known, and inside which silo.
See why for more common issues with silos in contrast to having your own website.
Many silos wrap any links posted on them with their own domains or link-wrapping domains, sometimes in an attempt to make links shorter, sometimes to provide a bottleneck which they can use to mass disable spam/phishing links.
- Breaks link referrals (you just see the silo wrapper, not the actual post that linked to your domain)
- Fragile for all the usual link-shorteners by a site other than the owner are fragile problem. As well as their typical use of database ids.
A number of individuals, prominent and otherwise, have publicly "quit" various silos
From time to time, silo projects are announced without shipping, and often never ship. As this list grows we can consider creating a separate vaporware-silos page.
- Cybe appears to be a splash screen and silo at cybe.me with a ton of rhetoric ("manifesto", "vision", etc.) but no product. Their Twitter hasn't been updated in over a year.
- ... add other silos that have been announced but not shipped, preferably with a citation to the announcement, preferably date-stamped.