20 microarticles about C# -- 2

MAX BUDGET: 20$ Need to write 20 micro-articles about C# 50-200 words each. Give code examples. Do not blindly copy-paste Stack Overflow or other forums. Rephrase at minimum. I will use a tool to find duplicates online before confirming that the work is done. Examples of article topics 1) Array vs List<T> in C# 2) How to convert string to double in c#? Obviously, your english has to be quite good, not broken.