Main Page

Explain xkcd: It's 'cause you're dumb.
Revision as of 10:19, 21 June 2013 by Markhurd (Talk | contribs)

Jump to: navigation, search

Welcome to the explain xkcd wiki!

We have an explanation for all 5 xkcd comics, and only 0 (0%) are incomplete. Help us finish them!

Latest comic

Go to this comic explanation

USB Cables
Tag yourself, I'm "frayed."
Title text: Tag yourself, I'm "frayed."


Ambox notice.png This explanation may be incomplete or incorrect: Cleaned up the section on "weird shape". Please change this comment when editing this page. Do NOT delete this tag too soon.

In this comic, Randall states the 'Law of USB cables': You will never have more than one which has no problems now matter how many you get. Now that most devices charge off USB, having a cable (specifically, USB-A (the big end) to Micro-B or USB-C (the small end)) is essential. However, most USB cables are cheaply made, and carrying them around quickly damages them. This comic lists some common (and not so common) problems with USB cables.

  • Carry power but not data - USB cables have separate data and power lines. To save money (and sometimes for security reasons), the data lines can be omitted. This means it can be used for charging, but not data transfer. Two cables are shown with this problem.
  • Carries data but not power - Not typically done, but it could happen if the wires or pins get damaged.
  • Too short - Another money saving wheeze, some devices ship with pathetically short cables.
  • Charges phone slowly - More likely a problem with the charger than the cable, but may happen if the wires are damaged. Refers to some chargers not delivering more than half an ampere. Could also be caused by thin wires which lead to a significant voltage drop, thereby reducing charging speed.
  • Won't auto-activate portable charger - Portable chargers (basically big batteries) should activate when the device is plugged in. Something about the cable (possibly the way the data lines are shorted) is interfering with this mechanism.
  • Has annoying ferrite lumps - Ferrite beads are used to filter out interference from the cable. High-performance applications need these, but on a phone charger you're just adding unnecessary weight and bulk. Two cables are shown with this problem.
  • Heavy and not very flexible - Either a heavy-duty USB cable, with thicker insulation, or a shielded one with a metal sheath inside to keep out interference.
  • Frayed - Cables experience a lot of bending force at the ends, near the connectors, and these can easily burst the insulation as shown here. Two cables are shown with this problem.
  • Plug doesn't fit through case - There's no standard for what the plastic housing around the USB connector should look like, and sometimes these are molded so they don't quite fit in the phone socket or through the charging port of an external case.
  • Needs to be twisted to keep working - The wires inside are damaged, and only connect when held in just the right way. One step away from total breakage.
  • Weird shape - The silhouette isn't very clear here, but it looks a bit like a Micro-B SuperSpeed, which has weird extra bits on it that don't fit the standard Micro-B socket. Or maybe it is just a normal USB cable but the connector is molded with a 90 degree turn (which is actually specified in the MicroUSB Specification, see pages 28-31) for no apparent reason and might be not convenient in some situations.
  • The good one - This is the one that really works out of the 15 shown, with 11 different problems. The funny thing is that it looks more or less exactly like at least 6 of the other 14. So it will take some time to find this cable.

The title text refers to the popular meme "Tag yourself, I'm..." which is used with pictures containing lots of strange phrases or other elements. People highlight individual details from the image with the phrase, usually self-deprecatingly. Here, Randall suggests that, like a USB cable, he's frayed. "I'm frayed" is also a pun on the sentence "I'm afraid" that is commonly added to the end of a comment which the speaker believes may leave a negative impression on the listener.


Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[15 USB cables are shown lying in a column. They are mostly very similar, with small differences. To the right of the cables there are 12 labels, as three of the labels belongs to three sets of two cables.]
Carry power but not data
Carries data but not power
Too short
Charges phone slowly
Won't auto-activate portable charger
Has annoying ferrite lumps
Heavy and not very flexible
Plug doesn't fit through case
Needs to be twisted to keep working
Weird shape
The good one
[Caption below the panel:]
The law of USB cables: No matter how many you get, you only ever have one good one.

Is this out of date? Clicking here will fix that.

New here?

Last 7 days (Top 10)

Lots of people contribute to make this wiki a success. Many of the recent contributors, listed above, have just joined. You can do it too! Create your account here.

You can read a brief introduction about this wiki at explain xkcd. Feel free to sign up for an account and contribute to the wiki! We need explanations for comics, characters, themes, memes and everything in between. If it is referenced in an xkcd web comic, it should be here.

  • List of all comics contains a table of most recent xkcd comics and links to the rest, and the corresponding explanations. There are incomplete explanations listed here. Feel free to help out by expanding them!
  • If you see that a new comic hasn't been explained yet, you can create it: Here's how.


Don't be a jerk. There are a lot of comics that don't have set in stone explanations; feel free to put multiple interpretations in the wiki page for each comic.

If you want to talk about a specific comic, use its discussion page.

Please only submit material directly related to —and helping everyone better understand— xkcd... and of course only submit material that can legally be posted (and freely edited). Off-topic or other inappropriate content is subject to removal or modification at admin discretion, and users who repeatedly post such content will be blocked.

If you need assistance from an admin, post a message to the Admin requests board.

Personal tools


It seems you are using noscript, which is stopping our project wonderful ads from working. Explain xkcd uses ads to pay for bandwidth, and we manually approve all our advertisers, and our ads are restricted to unobtrusive images and slow animated GIFs. If you found this site helpful, please consider whitelisting us.

Want to advertise with us, or donate to us with Paypal?