According to the text regarding skill shelf-life, what type of knowledge tends to last longer?

Answer

Foundational concepts

While specialized skills like a specific framework might have a short shelf-life (e.g., five years), deep, foundational concepts (like data structures) can last much longer (e.g., fifty years).

According to the text regarding skill shelf-life, what type of knowledge tends to last longer?
successcareerLongevityworkpath