What is a Internet Cookie?

If you logged into this site, you probably have a Wordpress authentication cookie in your web browser.  Unless you recently cleared it, your browser probably has dozens or even hundreds of these small pieces of code.  But what are they, and what are they used for?

Internet cookies are small pieces of code that are downloaded to your internet browser.  Usually, you get them from websites that you visit.  These cookies have many different functions.  Some of these functions improve the user experience, while others are potential problems.  For example, a very common type of cookie is an “authentication cookie”.  This is used to store login information.  Basically, this is one of several possible ways a website knows who is logged in.  While many modern websites do not use this method, in early commercial websites cookies were often used to keep track of what a user had in a shopping cart.

However, while most cookies are safe cookies may cause problems on your computer.  Cookies can be used to track things you do online.  They do not necessarily stop sending information when you finish using a site.  This can be a serious privacy issue.  For example, a website you visited months ago may still be receiving information from your computer.  This can be a risk to privacy and may open you up to security threats.

You may choose to block cookies from your browser settings.  Most internet browsers have an option that will allow you to block cookies.  Another option, and one I recommend, is to clear your cookies occasionally.  Many computer optimization software tools clear Internet cookies.

I hope this answers some questions and I hope you enjoyed reading this.

Please send me more questions in the comments section!

Brightening Photos Using the Brightness and Contrast Tool

This is my next post in my series of pieces on editing photos using GIMP.  For a full list posts in my series on editing images or other topics, you may use the tag or categories list at the bottom of this post or check the “Curriculum” link on this page.  This post is about brightening up a too-dark photo using GIMP.  None of the tools I am using are unique to GIMP and can be found in other image editors.

Brightening an overly dark photo is extremely useful when improving the looks of your images.  It is rare to have full control over the lighting when you are taking pictures and it is very easy to take pictures that are too dark.  Many photo editors have automated filters that can be used to brighten a dark image, however they do not offer the level of control that manual controls do.  For this tutorial, I will be using the manual brightness and contrast tool on GIMP to adjust the brightness of the image.  GIMP includes other tools that can also be used to modify the brightness of an image that will be covered in a future tutorial.  When modifying the brightness of an image, it is important to modify the contrast of the image as well.  This prevents the image from becoming too washed-out.

For this tutorial, I will be using a photograph I took outside on an overcast day that is far too dark.  If you would like to follow along on your computer, you can download the image below by clicking this link and saving it your computer, and try the tool for yourself on your download of GIMP.  Or you can use a dark picture in your computer to try the same techniques.

Start by opening the image in GIMP.

There are two ways to open the Brightness and Contrast Tool.  Both start by selecting submenus from the menu at the top of the screen.  The first is by going through the “Colors” menu and then selecting “Brightness Contrast”.  The second method is by selecting “Tools”, followed by “Color Tools” and lastly “Brightness Contrast”.  In either case, you open the Brightness Contrast tool.

As you can see, the tool has two sliders, one controlling brightness and the other controlling contrast.  Moving the brightness slider in a positive direction (to the right) brightens the image, and moving it in a negative direction (to the left) darkens the image.  The same applies to the contrast slider, with movements to the left decreasing the contrast and movements to the right increasing it.  The “Edit these Settings as Levels” button opens another dialogue that allows for more sophisticated manipulation.  We will be covering the use of the Levels tool in a later tutorial.  The preview checkbox should be checked.  This allows you to see the effects of your changes on your image as you make them.

I suggest starting off by playing with the controls a bit.  Try setting brightness to a high number while leaving contrast the same.  See how washed out and gray the image looks.  That is because brightness simply lightens the colors uniformly.  Even photographs taken in bright light have dark areas, which is why modifying brightness and contrast together is important.

Every image is different and there are no universal settings that will give you the perfect effect.  When working with your own images you need to experiment a bit to find the best values.  For this picture, I like a vibrant, high contrast look, so I set the brightness to 80 and the contrast to 75.  Try those values and see how you like them.  If you don’t, keep looking until you find values you like and then click “OK”.

And that is all there is to it.  Your picture is ready to use or edit further.

I hope you enjoyed this tutorial and post ideas for future ones in the comments!

What is a Vector Graphic?

Two terms you will encounter frequently when you discuss creating images on a computer are “vector” and “bitmap”.  Both are types of image and both have distinct uses.  You have probably encounter both types many times without noticing.  The primary difference between the two types is how the information is stored.  This difference leads to several important distinctions in how the images appear and how they are used.

In a bitmap image, which is sometimes called a raster image, the picture is in the form of pixels.  Each pixel is in a specific location and is a very specific color.  For example, a digital photograph consists of thousands of tiny squares which create images.

For example, just look at this photograph of some purple flowers.  It consists of approximately, 800,000 pixels and when you zoom in on it tightly you can see them.

Just look at this very tight close up on one of the flowers.  You can see around the edges of the flower where the pixels are visible.

All bitmaps store information in the form of pixels.  This has the advantage of being able to support very detailed images, that have realistic color variation.  However, this can also be a disadvantage.  As you can see, when you zoom in tightly on a bitmap, the you see individual blocks of color.  This is why there is often a limit on how much you can enlarge a photograph before it begins to look odd.  This is also why measurements like “dpi” or “ppi” (which stand for “dots per inch” and “pixels per inch” respectively) are relevant.  The more pixels in one inch, the more you can enlarge the image before it starts to look strange.

Vectors graphics work on a completely different principle.  Rather than storing the image as individual pixels, it stores the image mathematically.   Vector images are understood in terms of points, curves and mathematical formulae.  This allows for the storage of extremely complicated shapes.  For this reason, vectors are very scalable.  To increase the size of the vector image, simply adjust it mathematically and the image will be unchanged.  Vectors are excellent at shapes and designs.  They are frequently used in logos and drawings.  However, they do not work well for subtle color variation or photo realism.  Vector images often look like drawings or have a “cartoony” look.

For example, here is a very roughly created image of a similar flower.  It consists of five round shapes, each with a few additional points to give them more “petal” like appearance.

Obviously, this is a very crude graphic, but it does a good job of illustrating some of the characteristics of vectors that might not be as obvious in a more complex drawing.  Each “petal” is defined by six nodes and each node two other points determining the curve of the line connecting it to the next node.  The center of the flower is simply an ellipse.  However, because the shapes are defined by curves, when you zoom in, there is no change in the image.  You can zoom in as tightly as you like or increase the size of the image and the curves do not change.

This is a zoomed in look at one of the petals.  Notice how it keeps its shape and color.

Both bitmaps and vectors have many uses.  I enjoy working with both.

I hope you liked reading this article and please post your questions in the comments!

Note: Most webpages, including this one, prefer to handle bitmaps rather than vectors.  All of the vector images in this post were converted into bitmaps for viewing.

What is Open Source Software?

If you have been reading my previous posts, you may have noticed that I often direct people to various pieces of software.  I have pointed readers to a number of downloads, and keep a list of recommended pieces of software.  All of the software I recommend is free.  Some of the downloads I suggest, like CCleaner or Malware Bytes have both paid and free versions.  However, most of the software I recommend is open source software.  Open source software is almost always free, but this is not a requirement.

So what is the difference between open source software and other software?  Open source software is unique because the code (which is often called the source code) is available for anyone to access or modify to suit their needs.  Most commercial software is proprietary, which is also called closed source, which means that it can only be modified by the team that created the original work.  Open source software allows anyone to access the code and modify it.  Open source projects are usually highly collaborative efforts with many coders.  Open source software does have licenses, just as most other software, that prohibits users from doing things like selling the code.  However, users can make their own additions and are encouraged to, or in some cases required to, share those changes with others.  This often creates excellent programs that can compete with their closed source counterparts.

File Compression Or How to Zip and Unzip Files

This is another post in my series on essentials of dealing with files.  In this post I will be talking about file compression and how to zip and unzip files.  Compressing files is very useful when sharing files over a medium that has an upload limit.

All files stored on a computer have a specific size, which is usually given in bytes.  However, there are times when you would prefer files to be smaller.  For example, many email clients will only allow you to send files of a particular size.  This is a problem if you want to send larger files.  One solution to this is by using file compression.  This packages the files and makes them smaller.  However, in order to use the files they must first be unpacked.  There are many different types of compression software and many different compressed file types.  There are some differences, but most compressed files behave very similarly.  Compressed files can be identified by their file extension.  Common file extensions include “.7z”, “.rar”, “.tar” or “.zip”.  The most commonly used type is a “.zip” extension.  In order to unpack the file you need the proper software.  A Windows computer has the capacity to compress and decompress zip files preinstalled, but to use other types you will probably need to download software.  One of my favorite file compression tools is the open source tool 7-Zip, which has the capacity to handle many different types of file compression.  You can download it for free here.

If you are simply using zip files, you can use the software that is preinstalled on Windows computers to compress and decompress your files.

If you would like, you can follow along on your computer, just pick out some files that you would like to try zipping up.  There are many different methods that you can use, but I rather like this one.  You may wish to experiment a bit to see which methods you like best.

To Zip a File:

Start by finding some files that you want to compress. For this demo, I will be using some files I just created, but you can use any files you like.

Next, select all of the files that you want to compress.  To select more than one file, just hold down the Ctrl key before clicking on the file.  Then right click while the files are selected and click “Send to” and then click “Compressed (zipped) folder”.  Depending on your version of Windows these commands may look slightly different.  This creates a new folder that is “zipped”.  You may need to rename it, as it is by default named after one of the selected files.

You may notice on the screenshot, that there is also an option to select 7-Zip.  That is my favorite downloaded compression tool and it is used in a very similar manner.

Either tool creates a single compressed file that can be transferred far more easily than the original files.

Unzipping a File

Extracting a compressed file is just as easy as compressing a file.  If you using a zip file, you can use the preloaded software on Windows, but if you are using another type you need software.

When extracting the files from a zipped folder, first select the folder.  Then, right click and select “Extract all”.

Next, you need to select a destination file.  When you extract files, you create a new folder that contains the extracted files.

After that, you can access the contents of the file as you would normally.

I hope you enjoyed this tutorial, and please post other topics for me in the comments area!

Photo Editing Using the Clone Tool

This is the first post in my series on editing photos using GIMP.  For a full list posts in my series on editing images or other topics, check the “Curriculum” link on this page.  This post is about fixing problem areas in a photograph by using the clone tool in GIMP.  Other photo editors have similar tools, but for simplicity I will be demonstrating using GIMP.

The clone tool is one of my favorites for editing images.  How many times have you taken a photograph, but had something unfortunate sitting in it?  I will be demonstrating with an image of a blue sky with a power line stretched across it.  The clone tool is excellent for fixing this type of problem.  The clone tool copies the pixels from one spot on the image, called the “sample”, and allows you to place them anywhere else on the image.  You can cover up the problem by replacing it with small sections of other parts of the picture.  However, it does have some limitations.  It works best at filling in areas surrounded by the same color.  You cannot use this tool to fill in details, like faces or patterns.  It works very well for removing the piece of lint on someone’s clothing or a fly on the table.

If you would like to follow along, you can download the image below by clicking this link and saving the image to your computer, and experiment with cloning using your download of GIMP.  Or you can use a picture in your computer to try the same techniques.

First, open the image that you would like to work with in GIMP.

This picture is an excellent candidate for using the clone tool, because the cable is surrounded by sky that is all roughly the same color.

Next, zoom in tightly on a part of image with the power line.  You can do this by selecting the magnifying glass icon in the tool box and clicking on the image or by pressing the Z key on your keyboard.  The program zooms in by default, but you can switch to zooming out by pressing and holding the Ctrl key while clicking.

Here is a zoomed in version of the same image.  You will notice that the magnifying glass is selected, and that it is set to zoom in.

Then select the clone tool.  You can do it by clicking the small icon that looks like a stamp, or by pressing the C key on your keyboard.

Once you have selected the clone tool, you need to set a source.  This is where you will be copying from.  For this picture, you want to set your sample in the area of blue near the power line so that when you remove it, it is replaced by the same color of blue.

This is the tool options dialogue, where you set the size of the cloning brush. It will appear on the lower left-hand side of your screen, below the toolbox.  I prefer smaller sizes, and brushes with some transparency on the edges, but that is a matter of personal preference.  For this lesson, I will stick with the defaults.  However, you may wish to experiment with larger or smaller or different shaped brushes.

Once you have picked a brush that you like, hold down the Ctrl key, and click on the location on the picture you would like to copy from.  There will be a dashed area surrounding the sample location.  For my first section, I am going to take a sample from the area within the orange circle.

I am going to use that sample to fix the area immediately below it.  Once you have your sample, just click on the area you want to copy.  It may take a few clicks to fully erase a bit of the line.

This is what it looks like after the first bit of power line is removed.  Because I am using a fairly small brush, it took five or six clicks to remove a space that size.  However, notice how nicely the removed area blends into the sky behind it.

Once you have fixed a small area, move your sample location and start working on the next spot.  To move your sample, just hold down Ctrl and click on a new location.  Move your sample often.  It is not obvious, but there are significant color shifts due to lighting even on what you would think of as a surface that is only one color.

Also, if you click and drag your cursor, the sample moves with it.  Try it out.  Set your sample and then click and drag your cursor across the power line.  The sample moves with it.  This is useful in some cases, but may not always work, particularly if you are working  with a background that has distinct areas of color.

You can repeat what we just did until the entire power line is erased and all you have is a clear blue sky.

How did yours turn out?

Using the cloning tool takes a bit of practice, but is a very easy way to do simple fixes on photos.  I hope you enjoyed this tutorial, and please post questions in the comments section!

Saving and Overwriting — Or What is Difference Between Save and Save As?

This post is dedicated to a very common mistake that can cause a great deal of frustration when made.  How many of my readers are familiar with this scenario, I know that I certainly am.  You open up a document in a word processor.  The document is very long and you decide that you want to make a shorter version to print out and save the long one for an electronic version.  You delete a lot of text, some figures and a few charts.  You think you are finished and so you go to save the document.  Here is where horrible mistakes are made.  You are distracted, you click “Save”, because that is what you do with documents, and go on about your day.  When you go to get the long version out to print, it is gone and in its place is the much shorter version that you just created.  You have just been a victim of an overwritten document. If you had clicked “Save As” you would have stored your shorter version under a new name and instead of losing your original you would have had two separate documents.  This is why the distinction between “Save” and “Save as” is so important.

When you save something, you are replacing whatever currently exists at that file location with what you are currently working on.  This is fine as long as you do not want to access the old version.  When you use “Save as” you are creating a new file location distinct from the original one.  This allows you to have more than one version of the same document.

When dealing with the scenario we discussed earlier, it is sometimes possible to retrieve overwritten documents.  Some software, such as Microsoft Word, allows you to access previous versions for just this purpose.  Also, you may use backups or various software to retrieve overwritten files.

I hope this is useful and thank you for reading!

Image Creation and Editing Introduction

This post is the introduction to a larger topic on photo editing.  I will be talking briefly about my preferred tools for working with photos and where to find them.  I will be posting many short how to pieces on doing particular tasks using a photo editor in the future.  For my first tutorials, I will be focusing on using an editor for specific tasks, for example, brightening a photo, removing a bad spot, or fixing the color.

My prefer using open source software over commercial versions for demonstrations.  It is easy to find and widely available.  For my photo tutorials, I will be using GIMP which is an open source version of Photoshop.  You can download it here.  It is my favorite software for working with bitmap images.  For working with vector graphics I prefer Inkscape, which is an open source version of Adobe Illustrator.  You can download it at this link.  For my discussion on what vector graphics are, and how they differ from bitmaps, please click on this link.

For my photo editing tutorials, I am including an image for you to manipulate.  You may download the image and follow along on your own computer.

I hope you enjoy my tutorials!

Recycling Bin and Recovery — Or Why Simply Hitting “Delete” Isn’t Enough

This is another post in my discussion of managing stored files.  In this post, I will be talking a bit about deleting files and the difference between sending a file to the recycling bin and actually getting rid of it.  This is very basic, but extremely useful if you are like me and sometimes delete more than you want to.

You make like to follow along on your own computer here.  I am using a Windows computer, so some of instructions may be a bit different if you are using another type of operating system.

Start off by opening your file explorer, and select a file that you don’t mind deleting.  Right click it and select “Delete” or tap the “Delete” key on your keyboard.  Your computer will probably, depending on your settings, show you a prompt that asks if you really want to delete the file.  Allow it to delete the file, and it should disappear.  However, the file is not really removed from your computer.  Go to your desktop and open up your “Recycle Bin”.  The file you just removed should be sitting in there.  If you changed your mind and don’t want to delete the file, you can restore the file from here.

If you tap “Restore all Items”, all the files in the bin return to their original locations.  If you only want to restore a few things, select them and the click “Restore the selected items”.

As you can see, anything in the recycling bin can be restored with a few clicks.  However, you may want to actually get rid of some files, particularly if you are trying to free space on your hard drive.  In order to do that you need to empty the recycle bin.  The easiest way to do this is to simply use the button.  Once this is done, all the files that are in the recycling bin are, to some level, actually removed from your computer.  It may be possible to retrieve them using backups or system restore techniques, but this is one of the most commonly used ways to clear files.

One last note, some automated tools empty your recycle bin for you.  For example, I use a free tool called CCleaner, which in addition to several other tasks empties my recycling bin.

File Storage — Or Where Do You Store Your Stuff?

Good file management is very important to getting the most out of your computer.  There is a lot more to it than simply stuffing everything in your documents folder.  If you frequently use a word processor, work with photos, use spreadsheets or download anything you are constantly storing files on your computer.  The goal of this discussion is to help you understand where and how things are stored and to be able to adjust the storage method to make the best use of it.  This is not a technical discussion on various forms of storage, but an introduction to several basic storage methods and some pros and cons of each.

Most people have had at least one incident where a file is saved somewhere that is hard to access or lost it altogether. It is extremely frustrating to try to start working on a task and not be able to find the files that you need.  It is even more frustrating to work for hours on a project and then lose your work because you cannot find the file anymore.  So we are going to begin with a very simple issue- where are the files stored?  To explain that, I will be talking a bit about local v. external storage and what exactly is “the cloud”.

First, we will be talking about storing things on your local hard drive.  This is storage that is included on your computer.  If you have ever heard anyone talk about the size of their hard drive, this is what they are talking about.  In essence, the size of the hard drive controls how much “stuff” you can store on the computer.  There are advantages and disadvantages to storing things on the hard drive.  The biggest advantage is also the biggest potential problem.  The files exist on the machine.  The advantage is that you can access your files as long as you have access to your computer.  It does not matter if the internet is unavailable as long as you have your computer you can access your stuff.  That is also the big problem.  If your computer gets a virus, gets stolen, wet or smashed your files may be gone too.  You may be able to recover some of the files with some help from an expert or a removable hard drive but this is not guaranteed.  I have had a computer get a virus and permanently lost things.  This is why many people choose to make external back ups, just in case.

The second major type of storage is called external storage.  It consists of CDs, DVDs, portable hard drives, flash drives, and anything else you can think of that can store data.  They really all perform the same basic function.  You can store your files on these, rather than on your computer’s hard drive. This also allows you to move the files around.  If you want to move a file from one computer to another, you can store the it on a flash drive and access it from where you have the flash drive plugged in.  There are a lot of advantages to using removable storage, but there are some problems too.  Files stored on external drives are not taking up space on your computer, and are protected from being damaged if something happens to your machine.  However, all of these storage devices can fail themselves.  CDs, DVDs, hard drives and flash drives, can be corrupted by viruses, lost, fail, damaged by magnets or simply physically destroyed.

The last major type of storage I will be talking about has only become popular recently.  It is called cloud storage.  Cloud storage is a very popular buzzword, and you may have things stored in the cloud and don’t even realize it. Cloud storage, essentially, is files and information that is kept in another physical location and accessed remotely.  You upload a file to the cloud, it is stored on a server in some location and you access it from anywhere you are logged in.  Google Drive and Dropbox are popular cloud storage services.  Microsoft has their own paid cloud storage as do various other companies.  Some companies like Amazon or Google store things like pictures taken on their devices in the cloud.  You take a picture on an Android phone and it is uploaded to the cloud and can be accessed from anywhere you can access your Google account.  Cloud storage is great for convenience as the files are accessible from anywhere and are generally protected from things like a dropped or corrupted device.  However, you probably still want to keep local copies of important things.  If the internet is unaccessible or the service closes you do not want to lose your stuff.

So which one is best?

My answer, all of them.  For anything important, I like to store it in more than one place, because they are all vulnerable in different ways.  You need to experiment to find what works best for you depending on the project.