can you please help me understand this code better , I have some problems according left shft and right shift operands when it comes to setting bits

I have understood that const byte pin11 = 0x1 << PBit; // bit 3 means to set bit 3 to 1 but what is v = (PINB & pin11) >> PBit; // sense voltage at pin 11?

can you let me know how to understand setting bits.

#define PBit 3

 const byte pin11 = 0x1 << PBit; // bit 3 

 void setup() { DDRB &= ~pin11; // config pin 11 as digital input PORTB &= ~pin11; // disable pull-up Serial.begin(9600); // open serial port to host 

}

 void loop() { int v; 

 v = (PINB & pin11) >> PBit; // sense voltage at pin 11 

}

Serial.println(v); delay(100); 

// send voltage to host // wait 100ms