One of the keys to a successful presentation is including attractive images which make each of your points more dramatic. There is ample academic evidence that people have better recall for images than words.
When I make a presentation, ideally, I use a graph to represent the data behind a point I’m making. I can’t recommend strongly enough the works of Edward Tufte for advice on how to communicate quantitative data in graphics. However, unfortunately I often don’t have a pertinent dataset. When I don’t have pertinent data to share, I like to use a powerful photograph.
In picking images for a presentation, I find there are two main risks. The first is that I pick an image that is too easy for the audience to understand. An image of people holding hands together to represent teamwork falls into this category; it is trite and almost insulting. The second, and more dangerous, risk is using an image that is too creative and not obviously relevant to the topic. As Strunk & White said in the Elements of Style (paraphrasing), if you’re reading your own work and find a gem of a phrase that sticks out of your text, save it for future future, but delete it from your text as a distraction. My goal in presenting should be to find an image that is clearly relevant, but still clever and not overused.
Another important factor to consider (one that is often neglected) is whether I have the legal right to use the image. Most search engines do not have filters to distinguish between copyrighted and non-copyrighted images. Also, it is often difficult to know whether the image you are using is in its original form, or copied from another site. In addition, the page does not have to list copyright information for a picture to be considered copyrighted.
There are some some safe picture selection options, however. Stock photo services are numerous (e.g., iStockphoto), but they can be costly if you need a lot of images. To find free non-copyrighted images, I recommend search.creativecommons.org and flickr.com/creativecommons , which restrict your search to images that are licensed for use under Creative Commons. Just tick the appropriate boxes based on whether you plan to modify the image, and/or use it for commercial purposes. Another great resource for free images is Stock.XCHNG .
UPDATE from TechTracer 10 Most Amazing Google Search Tricks:
This is a most interesting trick. You might be needing images for various occasions and searching for images is the most difficult thing because what we expect might not be possibly mapped to a query. But Google has a parameter in place for images in situations we need an image which describes a face.
Suppose I search for the term "happy" then the Google results page displays smileys. But I would like to use images of happy people. Even if I choose the term as "happy face" the results don’t show images which contain people. For this there is a parameter "imgtype" which you can use with the URL. For this put in the URL as follows: