Strong gravitational lensing, producing multiple images of a distant background source owing to the gravitational deflection by a massive object in the foreground, has many applications in astrophysics and cosmology.
Gravitational lens systems are needles in a haystack but thousands are expected to be discovered from ongoing large imaging surveys in the optical. I will discuss the different lens searching techniques being developed and applied to the Hyper Suprime Camera (HSC) Survey. Over 200 strong gravitational lens systems have been discovered from early data release including highly compact galaxies. I will also present some early science results on properties of early-type galaxies such as the stellar initial-mass function and their environments.