First, we understand that it is not called iPhoto anymore. In fact it is simply called Photos in the newer versions of iOS, however, this could not have been named anything more confusing for consumers. Nonetheless, Photos or iPhoto is not an ideal place to store photos and unfortunately, if you are using a Mac photos will automatically download images into Photos or iPhoto the moment you plug in a phone, camera, iPad, iPod, etc. This is a problem but you don’t have to have it this way.
Why is downloading images into iPhoto/Photos?
If you are importing images into this program than you are storing images on your computer which is taking up hard drive space and therefore reducing your computers performance over time.
Stop the bleeding by turning off the auto import of images into iPhoto/Photos. Photonerds will show you how to do it.