Recently I started exploring Angular2 where I came across Typscript typings/TSD files with .d.ts extensions. I also noticed that we have type definitions already available for many libraries be Angular or jQuery. I followed a migration guide which asks to installs typings for angular and other related libraries.

So, if I have an Angular1.x project that heavily depends on third party libraries and we plan to migrate it use the next version of AngularJS and if the library does not have corresponding typings file available how should we create them ? Any guide or tutorial would help a lot.