http://ww1.microchip.com/downloads/en/DeviceDoc/70593d.pdf, here is the link for the data sheet it explains in section 9 as to configure COSC<2:0> of OSCCON register to one of the following. I am using primary oscillator with PLL it is represented as 011 as shown below. But when in code it is written as OSCCONbits.COSC!=0b011. I want know in value 0b011, I think that 011 represents the primary oscillator with PLL, but what is 0b which is attached as prefix to the value.
bit 14-12 COSC<2:0>: Current Oscillator Selection bits (read-only)
111 = Fast RC oscillator (FRC) with Divide-by-N 110 = Fast RC oscillator (FRC) with Divide-by-16 101 = Low-Power RC oscillator (LPRC) 100 = Secondary oscillator (Sosc) 011 = Primary oscillator (XT, HS, EC) with PLL 010 = Primary oscillator (XT, HS, EC) 001 = Fast RC Oscillator (FRC) with Divide-by-N and PLL (FRCDIVN +PLL) 000 = Fast RC oscillator (FRC)