system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Do Jedi/Sith feel any impact when deflecting blaster bolts with their lightsabers?
gpt
A blaster fires by a small amount of gas (often Tibanna) being energised and transformed into a beam of energy particles which is focussed and fired. A bolt would have fairly little mass, but due to the high energy it would still potentially cause some small impact on the deflection as it would hold kinetic energy. 

When deflecting the bolt a Jedi would probably feel enough impact to let them know they had successfully hit the bolt, but not enough to knock the lightsaber back. 

Materials which were hit by bolts would fare worse than a lightsaber (which, after all is deflecting and not absorbing the energy) as the energy could be transferred to the material and would do great damage to both organic and inorganic matter. 

*****

EDIT: There have been some more detailed explanations below about how the bolts damage materials and throw people back that are all v interesting, mine is rather over simple!