The term HODL refers to buy-and-hold strategies adopted by members of bitcoin and other cryptocurrency communities.
It all started as a drunken rant 🥃
Back in December of 2013, Bitcoin was on another huge upwards swing, from November to early December the price of BTC rose from around $250 USD all the way up to $1,151 USD. This massive 300x move to the upside led many to take to the Bitcoin forum to discuss various trading strategies.
One user by the name of "GameKyuubi" posted a drunken thread about their particular trading strategy with a topic title reading "I AM HODLING". This drunken typo filled post gave birth to the most well know Bitcoin trading strategy today HODL, which means to never trade your Bitcoin based on day-to-day action in the crypto markets.