How to add a photo in a topic

Can anyone please tell me how to add a photo in a topic?

And also how to use a photo which is already with a member of IF. I mean copy the photo which someone uploaded (ofcourse with the TM permission) to an topic.

for adding an image to the topic, you can upload it to any free image uploading site. Few well known sites are:

www.imgur.com
www.minus.com
www.imageshack.com

You will get in there as Forum Code, copy that code & paste it over here.

Using some one else's pic is simple, just save the image to your computer. Upload it using any of the above sites or any other free image hosting site of your choice.