Symplectic topology is the study of both rigid and flexible global phenomenon in symplectic geometry, which is the geometry of locally preserving the area. I will try to give you a feeling of what "symplectic" means through the study of symplectic embeddings : especially the famous non-squeezing theorem by Gromov (embedding a ball into a cylinder) and the case of 4-dimensional ellipsoids ; both leading to some global obstructions called "symplectic capacities". If time allows, I may describe few combinatorial aspects of symplectic capacities linked with the embedded contact homology.
P.S.: this talk might be interesting (for everyone I hope!) but especially for the M2RI's students who will follow the B1 advance course by J. Gutt.