What is the difference between <bgcolor> and <background-color>

Answer 1

Both of them with the tag mean nothing.
But without the tag, they are attributes.

Suppose a <div> tag you can use bgcolor inside it to specify it's background color like :
<div bgcolor = 'red'> </div>
Though this is obsolete and I won't recommend using it

background-color can be used in css like :

div {
background-color: red;
}

One is old, one is new but do the same thing

Answer 2

Okay, thanks