1. Normal pens we use have the ink in them. Have you ever noticed there is a tube in the pen that contains ink if you ever open a pen? Well there is difference right there. Dip pens get their names because you have to Dip your pen into ink. There is no tube in that handle that holds all of the ink. I know it sounds tiring but its actually fun. You can get Calligraphy ink at your normal art store or somewhere that sells art supplies.
2. Dip pens have different Nibs. What the heck are those?! Well they are the tips or the head of pen. The part where you write with. (Sorry I'm not really great at describing things!) Well once you finish with one Nib you can always wash it and use another one. You can just take it off and replace it with another one! Not like the normal pens we use. They don't come off at all! Unless you want to destroy you pen! (Thats always fun!) Each one has different tips and depths than others and have different puposes. Some are used for writing, like Calligraphy (thats why people call them Calligraphy pens!) or nomal writing. As I've said there are a whole different types of Nibs so you can always get one that your comfortable with. I use a specific one (I'm sorry I don't know what is called!) cause that one is required to draw manga with!
Oh I know the name!!!! I finally know the name!! My best friend gave me the G-Pen which most Professionals use to draw their art. I now know why Professionals use this one........its so hard figure what thinkness you want! I keep getting ink everywhere! I feel more comfortable with a Kabura Pen better......I find it better to draw lines equally unlike the G-Pen. You know Dip pens take a whole of practice and some types are hard to master. The first time I got a Dip pen I had a hard time getting used to it. Totally different from drawing with a pencil or painting. So don't get frustrated when you first start out!
I think I covered the major differences....hmmm.......yep I think thats it. I if you feel confused or still want to know more about Dip pens then feel free to comment!