As they say in the movies, "ooh behave". Seriously, though, we are trying to write an encyclopedia here, so don't make joke edits. Some readers looking for a serious article mightn't find them amusing. Remember, millions of people read Wikipedia, so we have to take what we do a bit seriously here. Now go and play a little in Wikipedia sandbox.   

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Welcome!

Hello, and welcome to Wikipedia. Thank you for your contributions.

Currently, you are editing without a username. You can continue to do so as you are not required to log in to Wikipedia to read and write articles, however, logging in will result in a username being shown instead of your IP address (yours is ). Logging in does not require any personal details. There are many other benefits for logging in to Wikipedia.

Please note these points:

 Please respect others' copyrights; do not copy and paste the contents from webpages directly.
 Please use a neutral point of view to edit the article; this is possibly the most important Wikipedia policy.
 If you are testing, please use the Sandbox to do that. 
 Do not add unreasonable contents into any articles, such as: copyrighted texts, advertisement messages, and texts that are not related to that article. Both adding such unreasonable information and editing articles maliciously are considered vandalism. A user who repeatedly vandalises articles will be blocked from editing.

The Wikipedia Tutorial is a good place to start learning about Wikipedia.  If you have any questions, ask me on my Talk page – I will answer your questions as far as I can! Thank you again for contributing to Wikipedia.

from Wikipedian: