This is Cyanobacteria, which in common parlance are called Blue-green Algae although they are not algae at all. They are on the other hand extremely ancient life forms, precursors of later life on Earth and by their photosynthesis led to the the presence of oxygen in the atmosphere. Thus without them mankind wouldn't exist either. Food for thought. Literally, as these organisms have high protein content and might be a future food source.