WEBVTT

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having the right tool for the job is important but how do you know exactly

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what the right tool is i mean it might be hard to figure out how exactly they

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make those cakes with the hole in the middle if you've never seen a bundt pan but your

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computer knows exactly what program it should use to open say a photo or video

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or a document basically every time that's thanks to today's unsung hero of

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tech the file extension not to be confused with browser extensions which

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you can learn about here file extensions are those two three or four letters you

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see after the file name when you're poking around your hard drive so doc

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mp3 and exe for example those are all

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file extensions see your operating system doesn't just analyze the internal

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code of a file and and try to figure out what it is that would be an inefficient

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and inexact process instead whichever program created the file will slap an

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extension onto the end to tell the os exactly what kind of data is inside for

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example if you've ever saved a document in word you've probably seen that drop

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down menu that lets you pick exactly what format you want the file to be

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saved in after you make your choice word will attach the appropriate extension so

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that Windows will know to use word if you've saved it as a standard word

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document notepad if it's plain text or adobe reader if it's a pdf when you open

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the file the os will check the extension against a list of file type associations

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you can bring up this list easily enough right here in Windows actually where you

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can see and modify which program is assigned to which extension now Windows

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will have a lot of default file type associations pre-loaded when the os is

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first installed for example it'll automatically know to use the built-in

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photo viewer app to load up a jpeg instead of trying to open it with like a

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music player or something but when you install new programs they'll usually ask

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if they should be the default program for opening certain file extensions

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especially with popular media applications like vlc which will present

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you with a long list of extensions that you can pick and choose from and

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extensions aren't just useful for getting your files to load up quickly

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they also help you the user see exactly what they are at a glance in the file

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explorer as Windows will assign little icons to your files solely based on what

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the extension is there are also times when it's useful to change a file

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extension especially if you've downloaded a file from the internet that

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you really want to get into it's possible that the creator of the file

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stuck the wrong extension on it or the file just doesn't have one at all so

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slapping a txt for example on the end of a mysterious file can at least get

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notepad to open it letting you have a peek inside to see or change an

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extension just disable this option in Windows 10. unchecking this box will

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cause file extensions to appear everywhere it's not a bad idea if you

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download a file you're not sure about in fact file extension trickery has led to

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some bad malware epidemics notably the

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love letter virus of the early 2000s the bad guy sent out an email with an

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attachment that appeared to have a txt extension fooling the user into thinking

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it was just a harmless plain text file but showing the extension in Windows

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explorer revealed it was actually a vbs file in other words a script that

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contained malicious code so be sure to pay attention to file extensions

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whenever you download anything and be especially wary if it's an unidentified

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exe or vbs as they have code that will

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run when you open them so be sure you know where they're coming from so tip of

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the hat to file extensions they can warn us about dodgy files and help our pcs

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run more quickly and because of that they are today's

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unsung hero of tech do you have an extra five minutes per day then use

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brilliant's daily problems to help you train your brain each problem provides

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the concepts by applying them if you like the daily problem then there's more

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like it in the quiz on the left so you can explore the concept in great detail

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and develop your framework if you're confused and need more guidance then

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join the community in discussing these problems these thought-provoking

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challenges will lead you from curiosity to mastery one day at a time the first

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sure to check it out so thanks for watching guys if this video sucked you

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can hit that button but if you liked it like the video get subscribed and be

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sure to hit up the comment section for with suggestions for other videos that

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you want to see in the future