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Title text: The hardest refresh requires both a Mac keyboard and a Windows keyboard as a security measure, like how missile launch systems require two keys to be turned at once.
|| This explanation may be incomplete or incorrect: This is chaos - multiple explanations should be merged and condensed. Do NOT delete this tag too soon.|
This Comic lists five different levels of refresh operations for web applications. The first three (soft, normal, and hard refresh) are different operations done in the browser to request that information be retrieved from the server. The other two (harder and hardest refresh) are further, imaginary operations that perform "refresh" operations on remote resources.
A "normal refresh" is a browser operation that reloads portions of a web page that have changed since the original load. It is the refresh operation triggered by refresh buttons in browsers, though can also be activated using the three common keyboard commands listed by Randall, and will generally accomplish the same thing as a soft refresh, with the additional cost of reloading the web page.
Hard refresh is a less common browser operation that clears any cached files associated with the page before requesting a new copy. Browser caching is a way to store webpage resources locally in order to decrease load time and data transmitted. Hard refreshes are usually used when a webapp has changed in such a way that the cached data is interfering with the proper display of the page. A hard refresh is slower because it forces the browser to download the entire page, but it ensures that the page is displayed as it is currently being served.
Interestingly, hard refresh HTTP request contains special headers (associated metadata) that command all intermediate proxy servers to drop their caches too. These headers can be seen by end application running on the web server, that can choose to reload some data from database and redo some long-running calculations in this case, even though this is not mandated by HTTP standard. In orchestrated environment it may indirectly cause some virtual machines to be rebooted. Rebooting actual physical server upon web page hard refresh is of course not normal, but additional processing may trigger some hardware or operating system bug that will cause exactly this.
"Harder refresh" is a joke that extends the existing naming scheme. The joke is that if a "hard refresh" resets the browser display and cache, a harder refresh should reset the source of the data by cycling power in the data center. Assuming no damage was done, this would reset the memory on the server, erasing any information that had not been written to disk, and setting the server to the state it was in at launch. This would cause considerable downtime, and would be unlikely to help the user at all.
The fifth option, "hardest refresh", moves beyond resetting the source of the data and resets the entire internet back to ARPANET, an early military network which was a forerunner to the modern internet. The implications of this are not made clear, but it should be noted that it wouldn't help to fix any problems a user is experiencing in-browser, as HTTP, the protocol by which web pages are sent, was not developed until late 1990, the year ARPANET was decommissioned.
The Keyboard shortcuts listed for the three real actions are, in fact, standard shortcuts. shortcuts tend to be longer and more complicated for less common operations, and the fake shortcuts play to this idea. The "harder refresh" uses six keys, including the non-standard 'HYPER' key, a feature of the Space cadet keyboard.
The "hardest refresh" shortcut uses fifteen keys, including non-standard ones such as Ø and ⏏. (The latter is the "eject" key found on [older?] Mac keyboards.) The shortcut makes amusing comparisons about a shortcut that includes not only the F5 function key, but also the keys for the letter "F" and the digit "5", as well as the similarity in appearance between O, 0, and Ø.
The title text suggests that the inclusion of both the windows key and command key in the "Hardest refresh" shortcut is a security measure akin to the Two-man rule, as it would require two keyboards to enter.
|| This transcript is incomplete. Please help editing it! Thanks.
| Refresh Type
|| Example Shortcuts
| Soft Refresh
|| Gmail REFRESH Button
| Normal Refresh
|| F5, CTRL-R, ⌘-R
|| CTRL-F5, CTRL-⇧, ⌘-⇧-R
|| Refreshes page including cached files
|| Remotely cycles power to datacenter
||CTRL- ⌘⊞⇧#-R-F5-F-5-ESC-O-0-Ø-⏏-SCROLL LOCK
||Internet starts over from Arpanet
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