[Salgat]

Learning a language in depth along with its extensive standard library can buy you months or even years of expertise. This is especially true in languages like C++ (a language with massive depth, such as template metaprogramming) or C# (a language with a massive set of libraries, ASP.NET alone can take years to truly master).

This is what companies are paying big bucks for, immediate competency and productivity.

[oblio]

The extensive standard library and the big libraries or frameworks that are the gold standards for their niches, in that language's ecosystem.

For example Hibernate for Java ORM, Spring as the big Java "LEGO brick bucket", Rail for Ruby web development, etc.