Reading analog data in connected to USB port (C#)

I'm taking over a project from a former colleague and was hoping someone could explain this code.

Task analogInTask = new Task();
AIChannel myAIChannel;
                    
myAIChannel = analogInTask.AIChannels.CreateVoltageChannel("dev1/ai0", "myAIChannel", AITerminalConfiguration.Rse, -5, 0, AIVoltageUnits.Volts);

AnalogSingleChannelReader reader = new AnalogSingleChannelReader(analogInTask.Stream);

analogDataIn_pres = -reader.ReadSingleSample();