Word etymology in computer science can be interesting. Most are knowledgeable about the origin of the word "bug" for example (An insect was found roasted to death inside a mainframe, causing short-circuits, that's what Grace Hopper called the first computer "bug"). Though the word has been is used at least since Thomas Edison's time. And when you must find the bug, you "debug", with a "debugger". Funny, right?

You may know that as most technological breakthroughs of the 20th century, computing was first started by the military, as an answer to the necessary war effort. And here we are, computing still has several words whose use was limited to warfare or military strategies before their advent in computing.

Staging

The staging area originally means the area where military personnel is stationing before going to mission. There dictionary says:

"Stage: To move (as military personnel, supplies, or equipment) to or establish in a new base in preparation for a further movement or a planned operation." —Webster's Third New International Dictionary

In computer science, it is used in several contexts. The mainly known use for contemporary programmer is probably the staging environment. Before an application is deployed into production, most businesses (hopefully) will thoroughly check/test the program in a staging environment before sending it to production use. Before sending anything into production, it should be battle-tested.

Staging area is a term used in the hugely popular VCS Git.

Git staging area can be quite confusing for beginners, but it is a powerful feature that allows you to selectively add changes from the working directory to the repository, using for example the git add --patch feature.

Deploy

As we just hinted at above, deployment is also a military term, designating the strategic spreading of troops on the battle stage.

Are we using military term too lightly? Probably not, when your business heavily relies on a web application, the right deployment of your application is critical to the success of your venture.

Cache

Cache is a very funny word, which has been used since the very beginning of modern computing. Myself included, I suppose no few people have been using the word without even thinking about where it comes from.

The first definition that pops ups on Dictionary.com is a hiding place, especially one in the ground, for ammunition, food, treasures, etc.. In computing, a cache is any kind of temporary storage space that allows fast access to data. For example, if you've seen this page before, some of its content has probably been cached by your browser so that it does not need to reload a data from the web. Indeed, accessing a PC's internal storage is much faster than getting contents with an HTTP request.

Foobar

Foo and bar are the widely used placeholder words used in code snippets and examples. When math-savvy people would use, x and y, computer geeks will use foo and bar, like in the following example:

/* C code */

#include <stdio.h>

int main(int argc, char* argv[])
{
   char foo[6] = "Hello";
   char bar[7] = "World!";
   printf("%s %s\n", foo, bar);

   return 0;
}

The etymology of foobar is obscure, yet it seems (at least according to wikipedia) that the FUBAR acronym was a slang used during World War II (Fu**ed Up Beyond All Recognition/Any Repair/All Reason). Foo is said to have been in used since circa 1900, and it is thus speculated that bar was added under the influence of WWII FUBAR. Whatever, if you need a third placeholder, baz should do the trick :).

By the way, did you know that Japanese programmers usually uses hoge or hogehoge as a placeholder name?

DMZ

A DMZ (De-Militarized Zone), apart from specifying a zone where no military action should be undergone (e.g. at the border of two countries at war), is a computing jargon which is used, as far as I know, in networking.

In networking, the DMZ refers to the subnetwork that responds to request from the outside (public) but that also has access to private components. We could say it is the middleman.

The most simple use case of a DMZ may be with a web application server fetching user data from a database. The web app server itself is in the DMZ and accessible by the public while the private database server containing sensitive data is not publicly accessible.

Ping

malik@my-pc:~/workspace/malikolivier.github.io$ ping -c 5 boussejra.com
PING boussejra.com (192.30.252.153) 56(84) bytes of data.
64 bytes from pages.github.com (192.30.252.153): icmp_seq=1 ttl=50 time=305 ms
64 bytes from pages.github.com (192.30.252.153): icmp_seq=2 ttl=50 time=286 ms
64 bytes from pages.github.com (192.30.252.153): icmp_seq=3 ttl=50 time=232 ms
64 bytes from pages.github.com (192.30.252.153): icmp_seq=4 ttl=50 time=290 ms
64 bytes from pages.github.com (192.30.252.153): icmp_seq=5 ttl=50 time=240 ms

--- boussejra.com ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4004ms
rtt min/avg/max/mdev = 232.139/270.924/305.335/28.924 ms

Phew, my blog may be online! Gamers might know ping because the use it to get a hint at the latency of the connection between their PC and the server. The ping command is mainly used as a diagnostic tool to check that a host is there in the network.

Ping turned back later to be a vulnerability (the Ping of Death), though any modern system is unaffected by such an attack.

Stating that ping is a jargon with military background may be a bit far-fetched, but let us not forget that the name of the ping command comes from the sound made by a sonar (PING!). And who else but the military uses a sonar? (Probably a lot of persons, but whatever.)