Analyze an embedded C program

What does this part of the code mean in terms of the "if" and "while" statements

void blinkLed ( int blinkDelay, int ledPin ) { static int blinkState = 0 ; static int blinkTime = 0 ; int currTime = millis ( ) ; if ( ( currTime - blinkTime ) > blinkDelay ) { blinkTime = currTime ; if ( blinkState ) { digitalWrite ( ledPin, HIGH ) ; } else { digitalWrite ( ledPin, LOW ) ; } blinkState = !blinkState ; } }

void beep ( int duration ) { int startTime = millis ( ) ; int currTime ; while ( ( currTime - startTime ) < duration ) { digitalWrite ( buzzerOutputPin, HIGH ) ; delayMicroseconds ( 500 ) ; digitalWrite ( buzzerOutputPin, LOW ) ; delayMicroseconds ( 500 ) ; currTime = millis ( ) ; } }