Digital Data
“If you can read this, congratulations—the archive you’re using still knows about the mouseover textâ€!
“If you can read this, congratulations—the archive you’re using still knows about the mouseover textâ€!
Digital information has the potential to be copied such that the copy is 100% identical to the original. While physical media themselves (such as books, or hard drives) and information stored by analog means may degrade as the universe continues, digital information as expressed by specific values, such as combinations of binary zeros and ones, does not decay over time and can be copied indefinitely with no changes.
However, in this comic, Randall points out that while digital information itself doesn't need to degrade, things that are on the Internet are often degraded through copying when the copy is not a 1:1 copy or changes are deliberately introduced. In addition, as technology advances, the method to save or call the information changes and the medium to view it changes, occasionally causing misinterpreted information. (This is also demonstrated with the mouseover text.) As the frames continue, they gain the appearance of images which have been screenshotted repeatedly, with a resulting loss of quality due to compression of the original resolution and JPEG artifacting. (The JPEG format is intended for representing photorealistic grayscale or color images; when misused for line drawings, such as comic strips, any compression artifacts become particularly noticeable, as the background is normally of completely uniform color.) In the last frame, this is taken to an extreme, as the frame appears to have been very sloppily screenshotted off of at least two different smartphones (not the same device that uses the bottom frame in the third panel as the top border in panel four), and the final image is covered both with a watermark from an unregistered screenshot program, as well as references to at least two different web sites: 9GAG (bottom right image) and Tumblr in the web address bottom left. 9GAG is an online platform and social media website where users upload and share content of their own, or of other networks. It is often accused of rehosting other sites' funny content without attribution and adding their own watermark to the image or video. Furthermore, the image ends up cropped, so that part of White Hat's last comment is left outside the frame.
As an easter egg, the high-resolution (pixel-doubled) version of the comic is merely the comic resized to 50% and then to 400%, making it an image of poorer quality rather than a higher resolution image as for other comics, demonstrating how repeated image scaling can also introduce artifacts into images. There appears to be another easter egg in which between 21 November 2016 and 10 December 2016 (both Internet Archive pages), the original hi-res image was replaced by the pixel-doubled image. However, the image URL below the comic still links to the hi-res image.
The mouseover text is seemingly addressed to a reader in the future who will only be able to access xkcd through a digital archive. Digital information might not degrade with time, but it can't be properly displayed without knowledge of the encoding. As new encodings and file formats get developed and old ones abandoned, the webpage format of the comic might not be available in the future, when users would need special archives to view content from today's world. The mouseover text contains seemingly garbage characters, which typically result from data being interpreted according to a character encoding different from the one used to encode it. In this case, the characters are the result of encoding the string “If you can read this, congratulations—the archive you’re using still knows about the mouseover text”! using UTF-8 (which represents non-ASCII Unicode characters as multibyte sequences) and then interpreting the resulting bytes as the still commonly used Windows-1252 encoding (which uses only one byte per character, but utilizes the non-ASCII codepoints for a limited selection of extra letters and symbols such as "â" or "€"). This shows that degradation of digital data through conversions isn't restricted to images. Furthermore, as screen navigation moves away from the mouse toward touch, voice recognition, and modes still to be implemented, mouseover text will itself become archaic. The garbage characters appeared later in the title text in 3003: Sandwich Helix.
