A welcome bonus is a bonus that a casino offers its players once they join their site. It's a way to appreciate new customers and encourage them to play. However, any winnings from the welcome bonus may have to be used to make other bets before any withdrawals can be made.
Israel is known as the "only democracy in the Middle East", and is a strategic ally of the west. Gambling is strictly regulated and mostly illegal. Technically, online and mobile casinos are also prohibited, but in practice, playing in foreign casinos is possible, and players are not actively prosecuted. This makes mobile online gambling casinos relatively popular.