OHLC stands for OPEN-HIGH-LOW-CLOSE. OHLC is a chart used by many traders and investors to analyze the performance of an asset for a specific time period. This time period can be 1 minute/2-minutes/daily/weekly/monthly/yearly based on your analysis requirement. Consider the image below for a better understanding.
The bottom of the vertical line is the LOW. It signifies how low did the price go during a specific period.
The top of the vertical line is the HIGH. It signifies how high did the price go during a specific period.
The left arm of the vertical line is the OPEN. It signifies where the price opened for that period.
The right arm of the vertical line is the CLOSE. It signifies where the price closed for that period.
If the open is below the close, as shown in the left line, it indicates an up market during that period. Similarly, if the open is above the close, as shown in the right line, it indicated a down market.