Question for Writers- Software/Programs.

I am wondering if any of you writers out there could tell me what Writing Software/Program you have found useful. It can be FREE or something you must PURCHASE. If you’ve had bad experience with one, please let me know in the comments. I’ll leave it there so I don’t influence your ideas by what I’m needing. Why? Because I may need something totally different than what I think I do.


Thanks in advance,