You're not seeing the electron itself... rather the artefact it creates, i.e. the expanded bubble. But it does indicate the paths the electrons are following.

It is possible now to visualise individual atoms and new ultra powerful microscopes like the recently installed TEAM 0.5 and TEAM 1 (currently being installed) at the Lawrence Berkeley Laboratory will further improve the resolution possible (0.05nm or half an Angstrom with TEAM 0.5).

I work in nanoscience and still find this incredible.

RS