WEBVTT 00:00:00.000 --> 00:00:05.580 you're on the internet let's say you want to watch an informative video on a 00:00:03.899 --> 00:00:09.960 technical topic so of course you open yet another window in your browser and 00:00:07.620 --> 00:00:13.980 you type youtube.com into the search bar or maybe instead you type 00:00:11.240 --> 00:00:18.140 dailymotion.com or Floatplane.com what all these websites have in common other 00:00:15.660 --> 00:00:23.939 than video hosting is their domain extension.com this is what we call a top 00:00:21.300 --> 00:00:27.779 level domain or TLD it's basically a code that instructs your computer where 00:00:25.619 --> 00:00:32.279 to look up the IP address of the website you're trying to find in the domain name 00:00:29.820 --> 00:00:35.840 system or DNS the big directory of everything the World Wide Web has to 00:00:34.380 --> 00:00:40.739 offer so if you're going to mail.google.com your computer will first 00:00:38.219 --> 00:00:45.480 go to the top level domain com then search the domain inside it Google then 00:00:43.379 --> 00:00:50.879 the subdomain inside that if there is one in this case mail the original 00:00:47.760 --> 00:00:52.980 decision to have the TLD come last was 00:00:50.879 --> 00:00:56.579 largely arbitrary at the time though with new modern autocomplete features 00:00:54.780 --> 00:00:59.940 it's handy to be able to just type in the first few letters of the domain or 00:00:58.020 --> 00:01:03.480 subdomain which are far more specific different tlds have different meanings 00:01:02.219 --> 00:01:06.960 and are grouped according to their intended purpose into five distinct 00:01:05.700 --> 00:01:12.000 categories some of which are pretty interesting first is the group for 00:01:09.000 --> 00:01:14.220 infrastructure tlds this group such as 00:01:12.000 --> 00:01:19.080 it is actually only contains one domain arpa arpa was the first domain created 00:01:17.040 --> 00:01:22.619 and is used for a lot of basic processes that allow the internet to function like 00:01:20.939 --> 00:01:26.700 reverse DNS lookups which allow computers to find the domain name that 00:01:24.360 --> 00:01:31.560 corresponds with an IP address next are generic tlds which are further divided 00:01:29.100 --> 00:01:34.979 into generic unrestricted and generic restricted the difference being that 00:01:33.299 --> 00:01:38.220 anyone can apply for a generic unrestricted domain while generic 00:01:36.780 --> 00:01:42.659 restricted domains have certain eligibility requirements for example 00:01:40.380 --> 00:01:46.979 restricted domains include dot Pro which is for accredited professionals like 00:01:44.640 --> 00:01:53.040 accountants and lawyers originally the only unrestricted TLD was dot info 00:01:50.720 --> 00:01:56.820 tldslike.com.net and Dot org used to be restricted domains for commercial 00:01:54.720 --> 00:02:00.540 entities networks and organizations respectively but the rules about who 00:01:58.860 --> 00:02:03.619 could register a domain and under them went largely unenforced and eventually 00:02:02.579 --> 00:02:08.880 just disappeared.com is far and foremost the 00:02:06.719 --> 00:02:14.220 most popular TLD on the internet with a 52.8 percent share of all websites the 00:02:12.120 --> 00:02:19.260 second most popular TLD is dot org with 4.4 that's why companies that operate 00:02:17.580 --> 00:02:23.040 solely on the internet are known as dot-coms they even named an entire 00:02:21.360 --> 00:02:27.540 Financial collapse after it this popularity is to the extent that users 00:02:25.200 --> 00:02:33.720 often misremember websites under other tlds as having.com extensions leading 00:02:30.720 --> 00:02:36.959 organizations like Wikipedia.org to also 00:02:33.720 --> 00:02:39.420 register wikipedia.com as a redirect to 00:02:36.959 --> 00:02:43.739 their main site other more unsavory actors like scammers might register a 00:02:41.760 --> 00:02:48.480 similar subdomain but under a different top level domain in order to trick 00:02:45.840 --> 00:02:52.620 unwear users into thinking it's a more trustworthy site a practice known as 00:02:50.640 --> 00:02:56.160 typo squatting the collaborative nature of the internet means that many tlds 00:02:54.239 --> 00:02:59.760 wound up being used for vastly different purposes than they were originally 00:02:57.900 --> 00:03:05.400 intended depending on the decisions of the The Entity charged with managing 00:03:01.860 --> 00:03:07.260 them one example is dot TV the TLD used 00:03:05.400 --> 00:03:13.140 by little-known website called twitch dot TV is not as one may assume a 00:03:11.159 --> 00:03:16.800 generic TLD for television shows and video streaming what is it then we'll 00:03:15.300 --> 00:03:21.360 tell you right after our word from our sponsor who you can find at grammarly 00:03:18.720 --> 00:03:25.140 using the everpopular.com TLD whether you're writing a script for a YouTube 00:03:22.680 --> 00:03:29.700 video or emailing your boss to ask for a raise ensuring you have proper 00:03:26.940 --> 00:03:33.360 communication and tone is key that's why we recommend checking out grammarly 00:03:31.200 --> 00:03:37.140 premium's tone rewrite suggestions feature Sven on the business team use 00:03:35.580 --> 00:03:42.180 this feature daily as it helps him ensure his writing is coming across as 00:03:38.879 --> 00:03:44.280 clear and as confident as he is I met 00:03:42.180 --> 00:03:48.060 the guy just he's confident and when he has to communicate hard deadlines to his 00:03:45.959 --> 00:03:51.480 clients grammarly has his back with their confident tone suggestions getting 00:03:49.739 --> 00:03:56.060 started is super easy all you have to do is install the desktop app log in and 00:03:54.180 --> 00:04:00.780 start typing go to grammarly.com techwiki to sign up for a free account 00:03:58.019 --> 00:04:06.840 and get 20 off grammarly premium today dot TV is actually part of the largest 00:04:03.900 --> 00:04:12.120 TLD group country code tlds which contain 308 domains country code tlds 00:04:10.019 --> 00:04:16.799 are typically restricted to Citizens residents and organizations with some 00:04:14.400 --> 00:04:22.800 presence in the associated country they include dot UK for the United kingdom.ru 00:04:19.799 --> 00:04:25.639 for russia.ca for Canada and the sadly 00:04:22.800 --> 00:04:31.320 neglected dot us for the United States dot TV belongs to the small island 00:04:28.199 --> 00:04:34.199 nation of tuvalu population 12 000 00:04:31.320 --> 00:04:38.820 primary export fish in the late 1990s the tuvalu government licensed use of 00:04:36.600 --> 00:04:43.800 its TLD extension for the purpose of marking television shows and used the 00:04:41.160 --> 00:04:48.419 proceeds to buy tuvalu's entry into the United Nations then there are sponsored 00:04:46.080 --> 00:04:53.960 tlds which need no Segway these are proposed and managed by private 00:04:50.340 --> 00:04:57.060 organizations these include 00:04:53.960 --> 00:04:58.199 domainslike.edu.gov and Dot mil which 00:04:57.060 --> 00:05:02.100 are restricted to educational institutions the US government and the 00:05:00.120 --> 00:05:07.199 U.S military respectively there's also dot triple X for other websites 00:05:04.919 --> 00:05:11.780 featuring Vin Diesel or not finally there are test tlds which are used to 00:05:09.419 --> 00:05:15.780 test software dot example Dot invalid.localhost and DOT test are 00:05:14.280 --> 00:05:20.820 reserved for use by the internet engineering task force and are not even 00:05:18.360 --> 00:05:25.620 installed in the DNS directory this is so that no current or future domain name 00:05:22.860 --> 00:05:28.800 registered in the DNS will conflict with one of these testing domains that's a 00:05:27.419 --> 00:05:33.419 lot of information but there's not going to be a quiz after this thank you for watching like if you like dislike if you 00:05:32.100 --> 00:05:38.039 didn't and if you'd like to know more about the DNS system and how it works 00:05:35.280 --> 00:05:41.360 check out this video from 2016. don't forget to follow And subscribe