HTML 5: Is it <br>, <br/>, or <br />?

Question

I thought HTML 4.01 was supposed to "allow" single-tags to just be <img> and <br>. Then XHTML came along with <img /> and <br /> (where someone said that the space is there for older browsers).

so how I'm supposed to format my code when practicing HTML5
is there any difference between <br> and <br/>

Answer 1

Both forms are accepted, as <br> well as <br/>. The number of spaces also does not influence.

Answer 2

No.