691: MicroSD

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That card holds a refrigerator carton's worth of floppy discs, and a soda can full of those cards could hold the entire iTunes store's music library. Mmmm.
Title text: That card holds a refrigerator carton's worth of floppy discs, and a soda can full of those cards could hold the entire iTunes store's music library. Mmmm.


microSD is one format of the Secure Digital memory card format, used in digital cameras, cell phones, and other devices. It is very small, only 15×11×1 mm, but can hold large amounts of data. The US dime in contrast has a diameter of 17.91 mm. When this comic was published in January 2010 the maximum capacity for microSD cards was 16GB. The current maximum capacity is 1TB (as of January 2021).

The main character in the comic (on the right) thinks about all the ideas that could be expressed by the data in the microSD card, or in a library. He feels not just reverent and intimidated, but sexually aroused by the thought. As he begins to touch it, his friend is disgusted by what might happen if he uses the card as some kind of sex toy, and does not want to help him locate the card if it gets "lost" inside a body cavity.

The title text seems to be the main character thinking about how much data the card holds, in terms of floppy disks and the iTunes music library, and feeling aroused by these thoughts.

Randalls claims in the title text do check out. A high-density floppy disk with a FAT format holds about 1.4 MB of data, and has dimensions of 90×94×3 mm, for a volume of about 2.5 cm³. A refrigerator carton is the large cardboard box that fridges are delivered in. A typical refrigerator carton may be 1800×700×700 mm, a volume of about 0.9 m³. So a fridge carton could hold about 35000 90mm floppies, or roughly 50GB. This is comparable to the storage on a single microSD card. A soda can (500 ml = 500 cm³) could hold 3000 microSD cards or store 50TB of data (3000TB today). However, the iTunes store claims to hold 35 million songs (as of Summer 2016), and allowing for about 2MB per song gives 70 TB of music. The claim that a soda can could hold the iTunes library seems to be unreasonable, but it was reasonable at the time.

Related to this topic is this xkcd What If blog entry.


[Cueball and a friend approach a table.]
Cueball: Hey, what's up?
Friend: Shhhhh.
Cueball: Hrm?
Friend: There's a microSD card on your table.
[A 16GB microSD card sits next to an assortment of coins for size reference.]
Cueball (out of panel): So?
Friend (out of panel): I dunno, high storage densities freak me out. A whole aisle of library shelves on something smaller than a dime.
[The two people stand near the table, the friend peering at the coins and card on the table.]
Friend: Libraries are unnerving enough-millions of ideas surrounding you, towering over you. These cards fill me with that same reverence, that same intimidation.
[Cueball stands alone.]
Friend (out of panel): ...that same faint arousal. Maybe I'll just touch it.
Cueball: If you lose that card I'm NOT helping you find it.

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Please include definition of refrigerator carton. Also, what is the average storage capacity of a floppy disk? 00:08, 19 May 2014 (UTC)

These days refrigerators come in cartons for safe storage. Also you can open them to store floppy discs, which is a lot easier than trying to load them in soda cans. Especially the unopened ones. -- Weatherlawyer (talk) (please sign your comments with ~~~~)

A soda can of then's microSD cards could hold the whole iTunes library then. A soda can of now's microSD cards could hold the whole iTunes library now. I do not see the issue or what seems unreasonable. 02:55, 8 September 2017 (UTC)