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what are file formats?

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File formats are the way information (data) is written on your computer.

We already know that all our documents, photos, videos etc are just files to a computer. A computer doesn't "see" that picture of your first child, it only "sees" an image file.

Now in order for the machine to store these files, they have to be written onto the computer.

You can think of file formats as being like human language. If I spoke French or German, I could have written this in French or German.

It would be the same information, just written in a different language, or a different format.

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    understanding file formats.

    When you save a file, a picture, a document etc, to your computer, it's saved in a format.

    The format is set by whichever program you've used to create the file. All programs have what's called a default format.

    But I'm getting ahead of myself. we first need to know a little more about what file formats are.

    So here goes.......

    Let's say I need to get these supplies from the shops.

    I'll make a list, a shopping list.

    But what language do I use.

    What language do I write the list in? What format do I use?

    English, French or German?

    bread, milk & butter.

    Well since I only speak one language (or format), I have no choice, I have to write it in English.

    I have to use the English language (the English format).

    Who knows what I'll come back with if I try to write it in French or German?

    Many of you out there will have 2 languages.

    You may well speak English & French, or French & German, all 3 languages or more.

    So you would have a choice of which language (or format) you used.

    That's exactly how File Formats work on a computer.

    Every file (picture, document, video or music track) has been created by a program.

    And that program, created the file in a particular format, a particular language.

    And just like human languages, there are thousands of file formats.

    languages and file formats.

    file formats in action.

    Try doing this on your machine.

    We're going to create a simple document in a program called Wordpad. It'll be saved in Wordpad's default format.

    Then we'll try to open that document in Notepad.

    Open Wordpad & then resize the window so that it's in the top half of your screen.

    Then open Notepad & resize it to take up the bottom half of the screen.

    If your not sure how to size/move a program window like this, you've probably missed this guide, Resizing a Program Window.

    wordpad on top & notepad beneath.

    In Wordpad type -

    Can you read this?

    Then save the file onto your Desktop with the file name "Wordpad doc".

    type "can you read this".

    That's just a single line of text. A very simple message. Notepad should be able to read it, right?

    Well let's see.

    In Notepad, try to open the file "Wordpad doc".

    Can't find it?

    No, neither could I.

    The reason we can't see the file Wordpad Doc, is because it's been saved in a file format (or language) that Notepad doesn't understand.

    just where is "Wordpad Doc"?

    Lots of programs will do this. Not just Notepad.

    If they don't speak the lingo, they simply ignore it.

    If they can't read the format, they won't show the file.


    make notepad show all file formats.

    As I said above, most programs will simply ignore file formats that they don't understand.

    But all is not lost. We can make Notepad at least try to open our Wordpad Doc file.

    At the bottom of the screen, click the small arrowhead in the file type box.

    Then click ALL FILES.

    This tells Notepad to show every file type (format). Even the ones it can't read (understand).

    click ALL FILES.

    After clicking ALL FILES, you'll see every file that you've got on your Desktop.

    Scroll through them and find "Wordpad Doc".

    Once you've found it, left click once to select it, then click the OPEN button.

    Well that's weird.

    well, can you read this?

    It happens because Wordpad is a much bigger program than Notepad.

    Wordpad can create (save) files in different formats (or languages).

    Wordpad's default format is called RTF (Rich Text Format).

    Poor old Notepad, though, can only read files saved in the TXT (text) format.

    Again, you can think of these formats as being languages. So you could think of Notepad as only having 1 language, while Wordpad is multi lingual.

    What we're trying to do here, is to demonstrate how file formats work, or don't.

    Do try it out for yourself, I know it sounds a little complicated, but you can do everything here.

    file formats.


    changing file formats.

    So Notepad had a go at reading the file, but made a bit of a mess of it.

    That's similar to handing me a note written in French, German or any language other than English.

    But what if we could translate the note?

    What if we could get Wordpad to save the file in a format (in a language) that Notepad understands?

    Can it be done, and how do you do it?

    As I said earlier, Wordpad is multi lingual. By that, I mean it can create (or save) documents in different file formats (or different languages).

    So let's help Notepad out. We'll re-save the file in Wordpad, but this time, we'll change the format that Wordpad uses to save the file.

    In Wordpad, left click FILE, then click SAVE AS.

    On the menu, left click PLAIN TEXT DOCUMENT.

    Change the file name to be "Wordpad doc 1" and save it to your Desktop.


    When you click the SAVE button, you'll probably get this warning box open.

    We'll come back to why this happens later, but for now click the YES button.

    click YES.

    Now go back to Notepad and try to open the file "Wordpad doc 1".

    WOW, we can see it without having to change the file type to ALL FILES.

    Go ahead & open it.

    open it.

    Now Notepad can read the document.

    It can do so because we told Wordpad to save the file in a format that Notepad can understand.

    So even though the actual message "Can you read this?" is exactly the same, it depends on which format (or language) it's saved in.

    Rather like our shopping list earlier.

    hoorah, notepad can do it.

    Notepad can only read or write in the Text File Format (txt).

    So any file that isn't written in this format is gobbledegook to Notepad.

    Wordpad, on the other hand, can read & write in several file formats. Including the Text File Format which Notepad uses.

    Re-saving the file so that Notepad can open it.

    Very easy to do, and a little satisfying when the message pops up.

    File formats 2.


    which brings us back to the save as window again.

    I bet you thought you knew all that could be known about the Save As window. Well it has one more little secret. One more more function that we can use.

    In all the previous guides we've been using Notepad to save simple files to play around with.

    And Notepad can only save a file in the Text File Format (txt).

    But most programs can save files in many different file formats. As we've just seen with Wordpad.

    Close Notepad out of the way and then maximise Wordpad.

    Click FILE and then click NEW, to start a new document (a new file).

    On the blank page, type something, anything will do.

    type something new into wordpad.

    Now click FILE, and then SAVE. Just as you'd normally do to save the file.

    The SAVE AS window opens.

    Underneath the FILE NAME box, you'll see the SAVE AS TYPE box.

    the SAVE AS TYPE box.

    We can read, SAVE AS TYPE, to actually mean, "Which file format would you like save this file in".

    Currently it says "RICH TEXT FORMAT (RTF)".

    That's the default file format in Wordpad. The native language for Wordpad to use.

    But we can change it. Oh yes we can.

    To the far right of the box, you'll see an arrowhead.

    Click the arrowhead.

    the file formats wordpad can use.

    You'll see a list of the file formats that Wordpad can use.

    • Rich Text Format (RTF). Which is Wordpad's default format.
    • Office Open XML Document.
    • OpenDocument Text
    • Text Document. Which is Notepad's format.
    • Unicode Text Document.

    Wordpad can save our documents in any of these file formats. It can also open any file written any of these formats.

    But here's the thing, just like different people read & write in different languages, so do computer programs.

    Notepad had problems reading the Rich Text Format (RTF). 

    why so many formats? I hear you ask.

    That my friends, would be a very good question.

    And it brings us back to that message that Wordpad threw up earlier, when we saved the file as a Plain Text Document.

    The Plain Text Document format that we were changing to is a very old file format.

    It's designed to handle just text.

    It has very few options by today's standards.

    And so Wordpad is warning you that, if you've done anything fancy in your document, it will be lost if you save it as Plain Text.

    warning, you are about to...

    Rich Text Format, however, can do more than just save text.

    Using  RTF you can whack in a picture.

    we have pictures.

    Different file formats allow us to do different things. Or maybe they simply work better than their predecessors.

    Sometimes several developers are working on similar projects at the same time, and so we get rival formats appear, think about VHS & Betamax.

    For us, here on this course, we don't need to know everything about file formats. We simply need to know that they exist. That they are there and how we can use them.


    ready to go?

    So now we all know a little about file formats. We'll need that info later.

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