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Load2Learn – Making curriculum materials accessible
Hello. Welcome to the Slow to Learn video on understanding file sizes.
All computer files have a size and the size of that file determines what you can do with
it. So let’s have a look at some of the principles that are important for understanding
that. File sizes are measured in bytes. But most files that you will see are at least
1,000 bytes. So 1,000 bytes is a kilobyte. 1,000 kilobytes is a megabyte. Pretty much
most of the files that you deal with will be in the range of megabytes. 1,000 megabytes
is a gigabyte and gigabytes are very large files, for instance video files. 1,000 megabytes
is called a terabyte. And most hard drives you buy these days are of this size at least,
half a terabyte but very often 1 or 2 terabytes. A terabyte is a lot of data. Different types
of files have different size ranges. So, for example, videos are different from Microsoft
Word documents that are different from PDF documents and those are different from audio
books or audio music files. In general, a text only document, a document that doesn’t
have any formatting will be in the range of maybe 10 or maybe 500 kilobytes. If you have
a word document with a lot of pictures, that can be 1-5 megabytes or even more. Photos
are generally in the order of half a megabyte to about 15 megabytes, depending on the quality
of the picture that you took and the type of camera you are using. Audio files are typically
in the order of 3 and more megabytes. So a typical song of a few minutes will be about
3 megabytes and a typical podcast or an audio book maybe as many as 50 or 60 megabytes,
maybe even more if it goes over an hour. Videos are typically in the order of 100 megabytes
and if they are of the size of a movie, they can be up to a gigabyte or even more.
Now depending on the size, there are different things that you can do with the file in the
way you handle it and share it. So for example, when you send an email, most emails shouldn’t
probably have attachments of much more than 5 megabytes, even though that size is increasing.
So 10 megabytes is still safe for many emails. But if you want to be comparable with all
your recipients, keep your attachments under 5 megabytes, and that is a total of all the
files attached.
For things you typically upload online, to be able to do it in a reasonable time, you
should probably aim to keep it in the lower hundreds of megabytes. A typical USB stick
or USB drive will contain anywhere between 2 and 16 kilobytes, even though the sizes
are increasing and you can now get 32 and 64 kilobyte USB sticks as well. A typical
hard drive these days will be 1 to 2 terabytes, even though some of the smaller notebooks
may only have several hundred megabytes to save money.
So what does all this mean? It means that in a typical email you can attach maybe 10
documents or so, or maybe 5 pictures, again depending on the size that could be quite
varied. The sorts of things you will want to upload are generally photos, MP3s or relatively
short videos. But if you are dealing with films or thousands of MP3s or pictures, then
you can use a USB stick to move those files around. But if you want to store hundreds
of films, or tens of thousands of documents or many many photos and MP3 files, then you
can only do that using a hard drive. Of course you can upload all of these things but it
could take you days or even months to upload the gigabytes of data on the internet.
So when you think about file sizes, you should really think in the ranges of between 1 and
5, or maybe 10 megabytes if you are dealing with word documents, photos and music files.
That is about the maximum of an email attachment. Where there are large photos or MP3s that
are over 10 minutes or maybe short videos of low resolution, then you are dealing with
tens to hundreds of megabytes. And over 100 to maybe 2 gigabyte you are dealing with films,
short videos and very high resolution, well that is also the typical size of a USB stick
or USB drive or the size that you can get for free from an online back-up service, such
as DropBox, SugarSync or GoogleDrive.
If you are downloading files from Sow To Learn, you may notice that some of the Word documents
you download are much larger than is typical. So for example, you can have a word document
that is as large as 150 megabytes, that’s almost like a small video. That is done to
preserve the quality of the included pictures because there are many pictures in those files.
But we are also offering a smaller version of those files with a reduced size, and that
means the quality of the pictures is slightly lower but it should be more than enough for
most uses, unless you need to print them in high quality.
So to summarise, the larger the file the more storage space you need. The longer it takes
to download it, the longer to upload it online. It also takes longer for the file to open
and longer for the file to save and some slower computers may struggle handling a very large
file. However, it is important to know that if you have more files on your computer, it
will not slow down your computer. Files are simply stored on a computer in a passive way.
What will slow down your computer is not having enough operating memory or RAM and that will
also make it slower to deal with a large file, but simply having it on a hard drive, assuming
you have enough space on the hard drive for the operating system to work properly, will
not slow down your computer. It is also important to remember when you are dealing with files
online that most internet connections have a much slower upload speed than a download
speed. So even though you may download a music file in seconds, it may take you many minutes
to upload it and for a large video file it could take hours. Sometimes it is important
to discover the size of an entire folder and you can do that if you right click on the
folder and choose properties and that will show you both how many files there are in
the folder and what is their combined size.
Thank you for watching.
Thank you for watching. For more tutorials or information about Load2Learn, please visit
load2learn.org.uk or contact us on 0300 303 8313
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