There is a difference between staying up late to finish a task or to check a social network one last time before bed and neglecting sleep so you don't miss anything new or to keep chatting online. Connecting with others is a great way to catch up with others or to increase your career network, but allowing it to take over time you need to rest negatively affects your energy levels. Staying up late, or forcing yourself to stay up all night to socialize online, also hurts your mood and may make you short-tempered or easily angered.
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