Many applications (in particular most games) offer a set of resolutions to choose from. Some of them are pretty open and allow basically every resolution the underlying system seems to be capable of, others are pretty restrictive and offer just a small set of resolutions. If the difference between offered and native resolution is too big, the application becomes hardly usable.
On my search for a solution, the amount of resolution-mods available and especially this thread made me curious: How does one find out where an application stores the resolutions it allows? And also, how does one find out what to insert instead?
Remark: I legally own (bought) the installers for all applications I want to experiment with. They are sold DRM-free and I do not redistribute any parts, it's just for my personal use. Therefore I assume, that my intent is perfectly valid.
EDIT: @BrandonBryant's comment made me realize that my question is to broad and I apologize for this. I don't think that I can improve my question much, since I don't really know what to ask for specifically. If it's not off-topic, any hint on "How to get started?" would be highly appreciated.