wordpress blog is not supporting HTML tags like <h1> <p>

[lemon_1800]

I write my first post using simple HTML tags like <hr>, <h1>, <p>, and if I see its output, it omits the sentences between the tag <h1>, and it removes the tag <p> after I save it in the page source. So I wonder whether wordpress blog does not accept html tags.

[Note: I inserted HTML tags using "HTML" tab, not "visual" tab]

[Psycho_MX]

You don't need to insert the html tags for HI, H2 and so. You can do it from the WYSIWYG editor. If they are not listed only click the MORE button and you will be able to write text in H1 format.

[lemon_1800]

Friend if I press "more" tab, it puts the following in the text box "<!--more--><!--more--><!--more-->" and if I press "code" tab, it puts "<code>" in it. May I know what that all is?
How can I write <H1> code using this "<!--more-->"? I hope someone will help me.