Summarize this article in one sentence.
Each website and application entails different social expectations, some of which may be unmentioned. Browse the Internet to determine what forms these expectations can take. It is often considered common courtesy, for example, to message a distant acquaintance on Facebook with a brief greeting before adding them as a friend. If a website or application does list any social expectations, of course, it is good practice to follow them. Many online forums, including the more updated and newfangled Reddit, will list their rules of engagement. Breaking these rules can lead to social exclusion and, at worst, banishment from the site or application. Note that online forums will often contain different messaging boards with their own unique sets of rules--don't presume that one subforum's rules will necessarily apply to another subforum. For example, Reddit's messaging board "askphilosophy" permits you to post open-ended questions, but its messaging board "philosophy" only permits you to post questions that are followed by some sort of argument or position. Meeting people online can be incredibly intimidating, but at some point the only way to succeed is simply by going forth and actually engaging people! Remember that the relative anonymity of the Internet means that you'll be able to retreat from uncomfortable situations at any time, which is helpful to remember if you end up needing to escape an awkward interaction. On the other hand, this same anonymity is what enables certain individuals to act more rashly or harshly than they otherwise would, and so it is important to disengage with these individuals and realize that their opinions have no bearing on the real, offline you. The anonymity of the Internet also means that you can never quite be assured of who you are dealing with. Never give out more personal information than you are comfortable giving out. Never agree to go anywhere or do anything that makes you feel uncomfortable. Trust your gut feeling about a situation. If you ever feel threatened, reach out out to the moderators of the website or application or find the link to report the individual in question. If you need additional support, you can contact a cyberbullying hotline managed by people who understand your situation.

Summary:
Familiarize yourself with the social etiquette of the website or application. Engage with the online community! Stay safe, and always proceed with caution.