I created a free account with IMGUR.com and upload my photos there. Then when I click on the photo when it displays, I can right click my mouse and copy the photo URL. I then paste that URL into the chat using the little photo insert icon.
I use IMGUR.com for only 1 purpose. And that is for posting images on internet forums. So, before uploading to IMGUR.com, I copy the photo from my computer photo software and then paste it into good old fashioned "Paint". I click the resize button and then resize by pixel size, so the longest side is less than 640 pixels so it meets the size requirement for most forum sites. After it get's resized I saved the image to my computer desktop (my default location) and then it's just a matter of dragging the image into my account with IMGUR.com.
It might sound like a lot of steps, but the entire process takes about 45 seconds. Plus, I have the images available for posting again, as I do use the same images, if the forum posts match, on different forums, or new postings on this one.
Because they are kept in order from newest uploaded to oldest uploaded. When the resolution size is 640 or less, the file size very small. You've got to remember, a computer screen will only display so many pixels per inch. Anything greater than that is lost. So, 640 works well.
I still have my original photos on my laptop, which are sometimes 10 mega-bytes large. Those are used for printing on paper where you really need the fine detail.
IMGUR.com is easy to use. And once you uploaded your first image, it gets even easier, and best of all, it's completely free.