A disciplined technique for restructuring an existing body of code
altering its internal structure without changing its external behaviour
Small restructuring, so itâ€™s less likely to go wrong
Make code neat so it’s maintainable and understandable
Small, independent learnable techniques to improve the code
When you have hammer & drill machine doesn’t mean you can hit anywhere and drill anywhere. It needs to be systematic, balanced.
There are around 300 formal refactoring technique

What is not refactoring

Code refactoring is not optimisation nor performance improvement. Code Optimization & Code Refactoring are discrete
We may end up making code faster or slower
Remember: We are making a strong house, the cost is going to increase as compared to building a house faster
It’s not intended to make the system faster; but ourselves faster as we can read, maintain, scale and fix the code faster. Adding features becomes very easy if the code is clean. In refactoring we don’t add features, we don’t change the observable behaviour of the application

Why we should refactor

You canâ€™t write perfect code in one sitting – Impossible
Remove future roadblocks. Avoid future bugs.
It’s not like the polishing underside of the table which is never visible. It always has a purpose
New joiner: he can start working immediately if our code is readable
Code is scalable, pluggable and detachable
Refactoring adds small risk and we will discuss how to reduce this risk in future posts