Warning: These terms are not officially endorsed by Maxis nor Electronic Arts, and are not accepted on Mod The Sims. Use of them in conversation without clarification may lead to confusion in the greater community.
Boddler-Induced Social Worker Infinite Loop Syndrome
Baby/Non-Baby Social Worker Glitch
The game, due to a glitch, mistakes a non-Baby character for a Baby. The Social Worker comes for the non-Baby and gets trapped on the lot, causing an infinite lock-up. This may be treatable with Simsky's Antidisasta Remote. Otherwise, the Windows Task Manager is your safest bet for dealing with this problem.
Corrupt Twin Birth Infinite Loop Syndrome
When this glitch occurs, the game locks up while waiting for the second twin to be born, and fails to execute the animation for the second birth. The game remains locked up because it is waiting for the second child to be born, which due to the glitch, will never happen.
Child-in-Trap-Induced Social Worker Infinite Loop Syndrome
Trapped Child Glitch
This is a rather easily-avoidable bug in which one cannot enter Buy or Build mode to remove the Social Worker or reposition the child, given she arrives to collect a neglected child who is trapped in a fence or wall structure that has no entrance. This can also happen if household objects block all logical paths.
Dead Child-Induced Social Worker Infinite Loop Syndrome
Dead Child Glitch
In the rare event that a Social Worker shows up to collect a Child and doesn't find him/her or leave the lot with the Child because the Child is dead. While the Social Worker usually doesn't do this, there are odds that a glitch can cause a Social Worker to pursue an already-dead child, which will lock up the game since she cannot claim dead children.
Vehicle Return Failure Infinite Loop Syndrome
When this glitch occurs, Nightlife vehicles fail to return to driveways properly, locking up the game and making it impossible for players to fix the problem. Thankfully, this bug is rare. It may or may not be related to a greater bug that has hit the game; one which causes inexplicable self-deleting of portals at inappropriate intervals. There have been patches made since, both by EA and by More Awesome Than You, in an effort to eradicate portal-deleting bugs.
Corrupt Lot Loading Failure Infinite Loop Syndrome
This is a problem that occurs when the lot you selected doesn't let you enter. The game locks up at the loading screen. This problem is usually caused by defective/corrupt custom content or custom content written for the wrong version. File corruption or bad design can be harder to detect, but filtering one's hacks usually locates the problem with time. Checking your custom files' version numbers helps to prevent damage from playing a hack made for the wrong game. Never use a hack or object designed for a different version than your own, unless it has cleared as being compatible and not conflicting. (I.e., A Free Time object will not work in a game that doesn't have Free Time installed.)
Music Role Switch Syndrome
Music Mode Glitch
This occurs when you switch between two game modes too quickly, and the game plays mode music for the wrong mode. This can be fixed by saving and exiting the game, and does not usually cause lock-ups.
Why do these distinctions matter?
Unlike twin baby glitches, which cannot be saved, instances of a Boddler can be saved before BI-SWILS is in full motion. Attempting to play Boddler-infected lots can result in BI-SWILS occurring immediately after loading, which can corrupt an entire lot and make that lot forever unplayable. If this unplayable lot is exported to a file, the file will be a virus which can corrupt other players' games.