Spain has a long history of gambling infact they gamble more per head (as a % of their income) then any other European countries! Similar to the UK you can bet on a huge array of things including the lottery, sports, betting shops, slots and scratchcards.
Spain has 20 casinos in the country and operate in much the same way as the UK, with roulette and blackjack being popular. You need to be 18+ (have your passport) and decently dressed i.e. no shorts or football shirts.
To play online operators need a special licensed to operate, this involves segregating the player pool from the rest of the world in order to pay taxes on profits. To gamble legally in the country you need to open an account with a site using the .es domain extension, many big sites pulled out of the Spanish market when these news were introduced in 2012 but since then several have renetred due to less competition and the Spaniards love of gambling!
Current big operators include pokerstars.es they have segregated the Spanish market so that all players in Spain play each other. bwin.es is the biggest operator in the country and sponsors real Madrid and bet365.es have also reentered.
Players may need to submit a copy of their official ID or driving license to prove their age. If you look at the bottom of each gambling website you should see the official license number of the operators, if they don’t display their license then they probably don’t have one so proceed with caution.
Players in spain can even use paypal to withdraw winnings