Reddit runs on votes and it's votes from the Reddit community that determine what gets seen and surfaced in communities and conversations across the platform.
Next to each post and comment you’ll notice little arrows. One arrow points up and one arrow points down. These are buttons that allow you to "upvote" or "downvote" content. Upvotes show that redditors think content is positively contributing to a community or the site as a whole. Downvotes mean redditors think that content should never see the light of day. If you like something, be it a post or a comment, and you think it contributes to a conversation, upvote it! On Reddit, that's just considered good manners.
If you have more questions that aren’t covered in these FAQs, check out r/help. Someone may have had the same question, or you can ask a new one and a Reddit administrator or one of your fellow redditors will help you out.