Your ledger gives you the option to choose whether you want to store your coins on legacy-address-format (Which is the original address format)
or on segwit-address-format (SegWit was implemented in a soft fork a few weeks ago).
You are free to choose which you want to use. SegWit has the advantage of lower fees due to transactions being smaller in size.
Both of them are safe to use, so its up to you which you prefer.
thx for the answer