Besides physics, calculus and these are a few things I don't understand:

Having a social media profile (especially LinkedIn) with no photograph.

People who want to be friends on Facebook and you don't know who they are.

People who want to be friends on Facebook, but who never speak to you in person.

People who only post to Facebook when they get engaged, married or have a child.

Sending LinkedIn invitations to random people you don't know.

Sending out a press release because the calendar says you should.

Communications experts who don't use or understand social media.

PR people who don't follow the news, at all.

Not having business cards or having business cards without crucial contact information.

Going to networking events and not networking.

80s inspired clothing. Didn't work then, definitely doesn't work now.

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