[header] How to open dll files [title] Understand what a dll file is. [step] A dll (dynamic link library) is a windows file that is used by program to call upon existing functions. Essentially, they allow windows and other programs to gain functionality without having to have that functionality built-in. 
[substeps] Dll files are an essential part of windows programming, and lead to sleeker, more efficient programs. [title] Know that the average user doesn't need to open or interact with dll files.