Should overlayed modal cover banner or shouldn't?

1. Why you shouldn't use modal?
2. What is the difference between overlay and modal?
3. Is it acceptable to open a modal popup on top of another modal popup?
4. Should modals be moveable?
5. Should modals have a close button?

Why you shouldn't use modal?

Modal windows are horrible, they interrupt the user's workflow, demand attention and block important information on the screen. The belief is that when users see a modal, they get scared and completely forget what they've been doing.

What is the difference between overlay and modal?

A modal is something where you are doing work inside that new box rather than in the content that's underneath it. So a sign-in form that overlays, that pops up over the rest of the content, but that doesn't allow you to engage with this content underneath it, that would be considered a modal.

Is it acceptable to open a modal popup on top of another modal popup?

Using a modal on top of another modal is a big red flag that something broke down in your workflow. If your workflow requires a second modal, you probably have some bigger issues with complexity within your modal. Remember: some of the best use cases for modals are focused, simple content.

Should modals be moveable?

Modal dialogs should be movable unless you have a good reason for them to be fixed in place.

Should modals have a close button?

Closing the modal: Always provide a clear close option for users by using a button or an 'x' icon at the top right of the modal.