While you may have image editing software on your computer, it's also worth knowing about some good online alternatives that allow you to do basic image editing - crop, resize, etc. - without having to install any software at all. That way, if you don't have image editing software on your computer, or if you are working on a computer in a public setting, in a computer lab, etc., you can still do some quick image editing!
One of the nicest online image editors that I have found is Picnik.com. All the basic services are available for free. There is also a Premium membership ($25/year) which gives you access to more powerful editing tools, a photo history (so you can recover previous versions of your photos, etc.), and it also removes the banner advertising from the site. I can't tell you a lot about the Premium version, but I can tell you that my experience with the free version of Picnik has been excellent.
When you start Picnik, you will see a basic editing screen that allows you to either sign in as a user, or simply start by uploading a photo from your computer with creating an account at all. There are also some demo photos you can play with to familiarize yourself with Picnik's features. One of the most common things I need to do with images is to resize them, which is very easy with Picnik:
The cropping tool is also easy to use, and for those of you who are serious photography buffs, you will appreciate the way the grid layout of the cropping tool encourages you to think about the "rule of thirds" as you select the crop area.
Cropping and resizing are the two features that I use at Picnik.com all the time, but you will see that there are all kinds of other editing options available in the free version of the software. So, if you have a photo you have taken yourself, or an image you have found on the Internet, you can use Picnik.com to tweak that image, so that you end up with the picture that suits your needs!
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