Code reuse: How to reap the benefits and avoid the dangers

Code reuse (or software reuse) is defined exactly as one would expect: reusing code that already exists either within your organization or externally when developing new software.
The existing code may be reused to perform the same or very similar function. There are varying degrees of code reuse, ranging from repurposing a small section of internal code to relying on large third-party libraries and open-source frameworks.