What is the correct way to name images (not SEO)?

Question

HTML

Actually there was a dilemma.
Is there any difference in how the image will be named, for example:
header-logo.png or header_logo.png
(use dash or underscore?).
And what better to do if the name of the picture is a little more? For example:
footer-ico-vk.png, or footer_ico-vk.png, or footer_ico_vk.png
Are there any recommendations on this topic? Is there any difference between the given examples?
Please answer how you and why give the name of the images.

Answer 1

no difference. as long as the names are clear