Armor is not a new concept to any civilization, having been a form of military equipment that has existed since the very onset of most civilizations, and a very simple one at that. Not many things are more simple than surrounding yourself in a material of any type to lessen harm received from an attacker. Throughout the development of warfare the material involved in granting this protection has changed, but the concept has stayed the same throughout the hundreds and thousands of years. In the current era, this mostly takes the form of various composites and alloys to offer far greater strength than any cheap material can offer.
Starship Armor[]
Due to the hostile environment of space, all civilizations that reach the interstellar age have at least some level of armoring protecting their vessels. In the case of military craft, the heavy layering of armor plate serves to protect against enemy weapons, serving as the second line of defense against all weapons fire. This plating can take on a vast assortment of compositions capable of serving various tasks - some more suited against kinetic resistance, some more suited to taking the impact from thermal weapons such as lasers. A notable quirk of heavy armor is that while it does take away maneuverability, the localized damage of armor makes it technically more powerful a barrier than a shield. While heavy fire will penetrate any one area of the armor with only a small fraction of the effort it takes to punch through shields, any damage is localized to a fairly small part of the hull instead of spread throughout.
Infantry Armoring[]
Infantry armoring is truly ancient concept going back to the dawn of any civilization seeking to reduce harm to their soldiers for an edge in combat. Be it just thick padding, steel plate, or a suit of composite fibers - the presence of armor has and always will be a constant throughout any civilization accustomed with war.
Standard Armor[]
In a starfaring civilization, typical armor is focused towards the goal of reducing the power of a kinetic weapon's likely-hood of killing a soldier, allowing for them to either carry on with the battle or be extracted without losing their life after taking a hit. These armors are generally composed of composite fiber compounds to disperse the energy of a bullet striking them, but also usually aren't able to take many hits.