S-bahn train from Frankfurt main airport to Hbf main station?

Simons explanatioin is right but a little bit weird so far. "Frankfurt Flughafen" - here stops the S-Bahn and regionla trains. "Frankfurt Fernbahnhof" here you can hop on far distance trains. Some of them stop at Frankfurt Hauptbahnhof as well.

There are two train stations at Frankfurt Airport: - "Frankfurt Flughafen Fernbahnhof", this is the station for long distance traffic, mostly by the ICE highspeed bullet train - you also can use them to go to downtown Frankfurt, but it will be more expensive than the S-Bahn commuter trains. - "Frankfurt Flughafen Regionalbahnhof", this is the station for regional commuter traffic, from here you can use the S-Bahn or other local trains (called RB or RE) to downtown Frankfurt.

There are two train stations at Frankfurt Airport: - "Frankfurt Flughafen Fernbahnhof", this is the station for long distance traffic, mostly by the ICE highspeed bullet train - you also can use them to go to downtown Frankfurt, but it will be more expensive than the S-Bahn commuter trains. - "Frankfurt Flughafen Regionalbahnhof", this is the station for regional commuter traffic, from here you can use the S-Bahn or other local trains (called RB or RE) to downtown Frankfurt.

I agree with rabit

It is Frankfurt Flughafen/Airport. There are local trains about every 10 to 15 minutes and you reach rankfurt Main Station within 11 minutes.

There are two train stations at Frankfurt Airport: - "Frankfurt Flughafen Fernbahnhof", this is the station for long distance traffic, mostly by the ICE highspeed bullet train - you also can use them to go to downtown Frankfurt, but it will be more expensive than the S-Bahn commuter trains. - "Frankfurt Flughafen Regionalbahnhof", this is the station for regional commuter traffic, from here you can use the S-Bahn or other local trains (called RB or RE) to downtown Frankfurt.

Hbf is the abbreviation for Hauptbahnhof (main or central station), often written as Frankfurt (Main) Central Station. It's the main hub.

At the airport, you follow signs to trains, direction city. You are looking for the S-Bahn. The S8 and the S9 (direction Frankfurt or direction city) both go to the Hauptbahnhof (main trainstation). You get the tickets out of the vending machine. Once you're there at the aiprot, it will make more sense. It's really pretty simple. You can also ask at an information desk at the airport if you feel worried or confused. You don't have to have it all figured out before you arrive. (why do you mention times for the bus?) The Sbahns leave very often. I wouldn't try to take the bus into Frankfurt.