Questionable Content was first posted on 1 August 2003, and currently updates five days a week; Mon.- Fri., usually between midnight and 6 AM Eastern time.
Despite the name, it is mostly work-safe, with only occasional exceptions. The humor is frequently crude and may be considered unsuitable for young children.
The events in Questionable Content center around the owner, employees, and customers of independent coffee house Coffee of Doom. QC has a large cast, to the point that even permanent characters may not appear for many strips at a time.
It is set in a world which has the same bands, stores, cars, medications, institutions, and celebrities as ours but which is oddly different. The QC world is internally consistent, although the author has left some loose ends in continuity. Events in the strip keep jumping into zaniness but the characters' personalities are realistic.
There has been a reduction over time in the number of references to music acts, formerly a major element of the strip.
There are many examples in the comic of characters struggling to overcome psychological issues and face their fears. In particular, overcoming social isolation and reaching out to others are often portrayed.
Underachievement is another recurring theme. Marten and other characters have dreams and goals which they haven't put enough work into. College-educated characters routinely work in low-paying service industry jobs.
Acceptance of diversity is another recurring element. The author has said "One of the major themes of QC, I think, is of inclusion".
The comic deals with many real-world issues, and with choices and consequences. This frequently leads people to react to what they see as the comic pushing an agenda. Jeph Jacques unambiguously dismisses such reactions in a post on the Questionable Content forum:
"It's idiotic bullshit like this that makes me tell people in the real world what a shitheap this forum is. Everybody's got an agenda and they're all trying to attach it to the comics. For future reference, if you're trying to divine some overarching moral standpoint from my comic: the moral of my comic is that people should try to be nice to each other."
For people who continue to take it too seriously even after that, the author has said "The purpose is to entertain people for 15-30 seconds every weekday and also to make me money so I can buy food".
- Main article: Guest Strips
Questionable Content sometimes features guest comic strips from other webcomics artists.
Questionable Content is one of the most popular webcomics, successful enough to be the sole support of the author.
The engaging characters and relatively good continuity are a jumping-off point for many people to play a game of treating the strip as though it were a documentary and analyzing it in detail. There are many examples of this here on the wiki. Players of this game understand that QC is a comedy in which things are exaggerated for the sake of humor, but who disregard this fact as being too boring. Forum member Dr. ROFLPWN put it well: "I also think it's important to step back, take a breath, and recall that QC is at its heart a lighthearted situational comedy where perpetual hipsters, nerds and a mad scientist's daughter share lives with porn-obsessed robots and Yelling Birds, and that if you view everything in it through the lens of Really Serious Drama, you are inviting nothing but constant heartbreak. Like life, QC should be enjoyed, and laughed at, not just the source of bitten lips and pursed brows."
As with all well-written stories, it is possible for readers to identify with the characters. This is often carried to the point of fans on the forum taking sides in arguments between the characters. The author seems displeased with this phenomenon. Forum user Odin points out "But then, when every single character in the comic is a walking bundle of psychological problems, it gets to be a bit difficult pointing blame at any particular person when bad shit happens."
Questionable Content has become the subject of many works of fan art, particularly around the fan favorite character of Hannelore. In addition, there have been several attempts on YouTube to recreate scenes and stories from the comics in the real world. Currently the most ambitious attempt is a feature length fan film  due for release in Winter 2011.
Jeph Jacques owns several domains, which redirect to Questionable Content:
- Questionable Content strip summaries by jwhouk
- wikified strip summaries, also from jwhouk
- Awesome complete cast list by jwhouk including minor characters
- Questionable Content transcript search (incomplete: ends at 1290 and is missing some in the 800s and 900s) hosted and implemented by Ryan North
- Comic timeline by Tybalt
- Timeline by Darkbluerabbit
- Timeline by LeeZion
- Count of each character's appearances through Feburary 2008 by Raoullefere
- The same count, here on the wiki
- List of crossovers from other strips
- Reader-chosen favorite episodes
- Questionable Content Fan Film Trailer
- TVTropes page on Questionable Content
- TVTropes forum for discussing Questionable Content
- Wikipedia article on Questionable Content