Own code in Wordpress header

Let us say I wanted to access the header of my Wordpress blog and stick some code in it, like an embedded 开发者_C百科youtube video and Facebook brand page. How and where would I do this?

In other words, instead of the usual image I would like my own content and then for the blog to start below it.

Any help or questions welcome. Thanks!

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You can edit the header.php file directly. This is a pretty messy solution though. It may be better to register a sidebar in the header and then use a widget to place a block of text/html in there. This way will allow you to manage the content of that area directly from the administration backend rather than having to vi into the header file each time you want to make changes.