Piennittoick80
Well, as a general rule of thumb, 1st class tickets are usually twice as expensive than 2nd class tickets.
With a 1st class ticket, you may also sit in 2nd class, especially where 1st class compartments/coaches are not available (e.g. buses, cable cars, funiculars, some cog wheel mountain railways)
With a 2nd class ticket, you’re not allowed to be in a 1st class compartment, not even just standing there.