Everyone has witnessed a pond of lake overrun with algae at some point, but what exactly is algae? According to Wikipedia, algae is a diverse group os simple, typically autotrophic organisms, ranging in many different forms.
Algae can be unicellular to multicellular which controls how long algae can grow to. For example there is a species of giant kelp that grows to be 65 meters in length. Seaweed is actually a form of algae and is the most complex form.
Algae also exhibits a wide range of reproductive strategies from simple asexual cell division to complex forms of sexual reproduction. This is probably why algae is so difficult to remove from your pond or lake.
Algae is just about as interesting as it is appealing to look at. If you have an issue with algae in your pond or lake the best thing to do is to contact some sort of lake maintenance professional that can help you clear it away.