Break Image Caching In Browser

No code, because this is mostly conceptual: So I've got a folder of images named thusly: 1.jpg 2.jpg 3.jpg 4.jpg These images populate a gallery, and as you might assume, the order

Solution 1:

append random string or time at the end or the image url -

/images/1.jpg?anythinrandonghere

If caching is specific to user or something else then

/images/1.jpg?username