This might seem confusing at first. You might not get it today or even tomorrow. It’s okay. It will start to click and become more natural. I know. I was the same way.
What is ISO, you ask? It is the digital equivalent of film speed. The higher the ISO is, the less light needed to make the exposure and the faster the shutter speed is. Also, the higher the ISO is, the more grainy your image is going to be.
If you honestly know what I’m talking about in the above paragraph, kudos to you. Most likely, though, you didn’t really understand. That was the photography savvy way of saying things.
Here is the photography savvy definition of ISO in a more understandable form. Say you were taking a photo of someone, but the place you were in/at was dark. Turn up your ISO. It will let in more light in darker lighting. Therefore, when you have brighter lighting, you can turn your ISO down. Beware, though, that if you turn up your ISO too much it can make the photo grainy and/or you’ll need a tripod. In most cases, that won’t happen, though.
Every {digital} camera should have an option to change the ISO. It doesn’t matter if you have a point and shoot or a larger camera. Dig out the manual and go into the menu and find it.
Play with the ISO! I would really enjoy seeing your photos! Upload them to someplace like Flickr or email me with them. I really do want to see them! If you have some questions, concerns, or general comments, please leave them in the comments. 
