Lightning sign next to block

Hello guys, quick question, I have created a block and it has a little lightning logo next to it, I have never come a cross this, when I click on other blocks, the logo doesn't appear. Why is it there? Thanks

The lightning bolt means that the block is a dynamic block. However as you created it, it wouldn't be dynamic unless you made it so. Strange

What is the difference between normal and dynamic block? thank you for your reply

A normal block is a rather static representation of one item, which can be scaled, possibly exploded, and or edited in the block editor, but that is about it.

A dynamic block has added attributes which are called parameters, enabling substantial changes to be made in many features, dimensions, orientations in particular predefined ways which

greatly increases its usefulness. For instance a block of an Entry door might have a width parameter, enabling you to change that width dimension on the fly, so to speak. Or it might have a drop down list of available widths defined, restricting you

to use one of those. Additionally it would include a FLIP parameter so you could reverse the hinge orientation, and likely a height parameter too.

You should be able to double click on it, which will take you to the Block Editor, where you can delete the dynamic parameter, and save it again, which will make it a regular block.

Thank you very much guys for you information and responses. I understand the difference now