Output anything to wp_head()

Hi,

I can’t seem to find an answer to this or perhaps I’m looking for the wrong question. I’m diving into making WP plug-ins starting with easy stuff.

Can anyone tell me how I output something (anything – even just a line of text so I can see it work) to wp_head() with a plug-in? Basically I wan’t it to output as soon as the plug-in in activated.

Thanks in advance.