Survivability means that something is able to keep going even when it faces problems or challenges. It's like when you learn to ride a bike and you fall down, but you get back up and keep going. You didn't give up even when it was hard.
In the case of something like a building, survivability means that it can resist damage from things like fires, earthquakes, or bombs, and still be able to function and keep people safe. It's like a superhero building that can withstand tough situations and still come out strong.
People also talk about survivability when it comes to things like diseases or accidents. If someone has good survivability, it means that their body is strong enough to fight off a sickness or heal from an injury.
Overall, survivability is about being tough and resilient in the face of challenges, and being able to keep going no matter what.