This is also one of new things in our forum. Everything is simple actually.
You (or random guy) having a problem/question and you come here asking what you need. Then people replying here and other guys upvoting/downvoting the replies. Staffs deciding which reply is the solution (based on if the thread poster's problem solved with that or it is just a real solution)

As you see on picture, i reacted it with "upvote". Most upvoted replies goes up, doesn't matter when it is posted. Then i choosed it as a solution. This is how it looks after all :

Well, not really very important future but still interesting thing for my opinion
You (or random guy) having a problem/question and you come here asking what you need. Then people replying here and other guys upvoting/downvoting the replies. Staffs deciding which reply is the solution (based on if the thread poster's problem solved with that or it is just a real solution)

As you see on picture, i reacted it with "upvote". Most upvoted replies goes up, doesn't matter when it is posted. Then i choosed it as a solution. This is how it looks after all :

Well, not really very important future but still interesting thing for my opinion