What exactly is 'bias' in the context of the program?

[anansrivastava]

I have no idea what bias is in the genetic.js. Is it a keyword?

crossOver : function(parentA, parentB) {
		var cutPoint = this.random(0, parentA.neurons.length-1);
		for (var i = cutPoint; i < parentA.neurons.length; i++){
			//what is the bias part. what does it mean
			var biasFromParentA = parentA.neurons[i]['bias'];
			parentA.neurons[i]['bias'] = parentB.neurons[i]['bias'];
			parentB.neurons[i]['bias'] = biasFromParentA;
		}

		return this.random(0, 1) == 1 ? parentA : parentB;
	},

Similarly, is connections a keyword? What is this achieveing?

mutation : function (offspring){
		for (var i = 0; i < offspring.neurons.length; i++){
			offspring.neurons[i]['bias'] = this.mutate(offspring.neurons[i]['bias']);
		}
		
		//is connections a keyword?
		for (var i = 0; i < offspring.connections.length; i++){
			offspring.connections[i]['weight'] = this.mutate(offspring.connections[i]['weight']);
		}
		
		return offspring;
	},

Also, the function 'activate' is not referenced anywhere. I am not sure if that is a keyword because intellisense didn't pick it up. Could somebody tell me how the activate function working?

activateBrain: function(bird, target){
			var horizontalDistance = this.normalize(target.x,700) *this.SCALE_FACTOR;
			var verticalDistance = this.normalize(bird.y - target.y,800) * this.SCALE_FACTOR;	
			var inputs = [horizontalDistance,verticalDistance];
			//not sure what activate is
			var outputs = this.Population[bird.index].activate(inputs);
			if(outputs[0] > 0.5) bird.flap();
	},

Would appreciate if somebody could help me understand these 3 things. Thank you so much.