what does "CACHE STRING" in CMake CMakeLists file mean?
<p>I came to this sentences in a CMakeLists file, I googled it but couldn't find relevant resources on the word <code>CACHE STRING</code>.</p>

<pre><code>set(CMAKE_BUILD_TYPE Debug CACHE STRING "set build type to debug") 
</code></pre>

<p>What does it mean? And imho, isn't this quite obscure to use?</p>