is <th> a <tr> ?!

Question

is it a subtraction of that?

Answer 1

@Brent
I understand now why when we color the table we put the tr tag for CSS styling. Thanks.

Answer 2

These are table cells.
<th> used for table header

<tr>
used for element of the row

<td> used for table data cells

Answer 3

@Martin @Brent
That actually occured to me when inputing color in the tr's style. I thought if we put color only in tr's style th's color would also be applied, then th is a tr itself!