Defence systems

There are 4 primary defence systems employed by starships although many other systems and design considerations also contribute to the survivability of the vessel.

Armour
This is the most misunderstood defence system by the general public because it relates as much to general toughening of the vessel's structure via bulkheads, force redirection and pressure management as well as the outer hull penetration resistance expected. For lower armour levels it is easier to picture this "armouring" as the collision resistance incorporated into ground vehicle designs.

A ship's electronic warfare systems provide both an offensive and defencive capability
Passive Emissions Masking

Other considerations
Radiation screens provide protection

A ship's weapons may protect against missiles by destroying them prior to detonation