function youtube_embed(video_id)
{
    var youtube_link = "http://www.youtube.com/v/" + video_id + "&hl=en_US&fs=1&rel=0";
    return '<div class="video_div"><object width="425" height="344"><param name="movie" value="' + youtube_link
        + '"><param name="allowscriptaccess" value="always"><embed src="'
        + youtube_link + '" type="application/x-shockwave-flash" allowscriptaccess="always" width="425" height="344"></object></div>';
}

function chord_image(chord_name)
{
    return '<div class="chord_image_div"><img src="/images/' + chord_name + '.gif"></div>'
}

function next_link(page_name, link_text)
{
    return '<div class="next_lesson_div"><a href="' + page_name + '.html">>> ' + link_text + ' >></a></div>'
}