I have hardly a year's experience in coding. After I started working, most of the time I would be working on someone else's code, either adding new features over the existing ones or modifying the existing features. The guy who has written the actual code doesn't work in my company any more. I am having a hard time understanding his code and doing my tasks. Whenever I tried modifying the code, I have in some way messed with the working features. What all should I keep in mind, while working over someone else's code?
Working on someone else's code
architecture;coding style;coding standards;coding;maintenance