factory design pattern vs abstract factory design pattern

Im so confused about what is the actual difference between abstract factory pattern and factory pattern. I had gone through this Stackoverflow reference question but couldn't reach in a conclusion.

public abstract class AnimalFactory
{
    public abstract Animal CreateFish();
    public abstract Animal CreateBird();
    public abstract Animal CreateMammal();
}

public class AfricanAnimalFactory : AnimalFactory
{
    public override Animal CreateFish()
    {
        return new Reedfish();
    }

    public override Animal CreateBird();
    {
        return new Flamingo();
    }

    public override Animal CreateMammal();
    {
        return new Lion();
    }
}

As per the example given, can the below code be shown as factory pattern?

public abstract class AnimalFactory
{
    public abstract Animal CreateFish();

}

public class AfricanAnimalFactory : AnimalFactory
{
    public override Animal CreateFish()
    {
        return new Reedfish();
    }

}

I had seen many questions which have been answered theoretically. im looking for a code wise explanation on this.