Detailed information can be found on the Spanish page.
Do I need a Schengen visa?
For other nationalities, please refer to the list on the webpage of the State Secretariat for Migration (SEM).
SEM – Overview of ID and visa provisions according to the nationality (Annex 1, List 1: nationality)
If you are obliged to hold a visa, please apply for it and refer to the information on the webpage:
Where to apply for a Schengen visa?
If you are not obliged to hold a visa, you are allowed to enter Switzerland resp. the Schengen territory and stay up to 90 days within a 180-day period without any visa.