The Series 7, or the "Registered Representative Series 7" is the national license required to be held by all investment professionals who are in the position of buying and/or selling stock, bonds, options, etc.
The test is given by FINRA, the Financial Industry's Regulatory Authority.
The Series-7 generally requires a minimum of 8 weeks of prep time, multiple existential crises, and sleepless nights filled with dreams about the stock market.
It requires intense level of memorization, specifically of acronyms, and sometimes results in calling loved ones by the wrong name.
"I love you, Cboe..."
'What did you just call me?"
"Chicago Board of Option Exchange... Sorry, Sarah... it won't happen after I'm done with the Series 7..."