Can someone help me decode this error message? Anytime I try to upload an image into my Blog I get this error:

Warning: move_uploaded_file(/home/christer/public_html/blogs/media/12-13-01.gif): failed to open stream: Permission denied in /home/christer/public_html/blogs/admin/b2upload.php on line 145

Warning: move_uploaded_file(): Unable to move '/var/tmp/phpwsIXnF' to '/home/christer/public_html/blogs/media/12-13-01.gif' in /home/christer/public_html/blogs/admin/b2upload.php on line 145
Couldn't upload your file to: /home/christer/public_html/blogs/media/12-13-01.gif