If you are married to a Thai citizen then you can apply for a Marriage Visa in Thailand. This initial visa is single entry which means that you are allowed to stay in Thailand for 3 months when you enter the Kingdom. It can also be extended.
The Thai Tourist Visa is the most used visa in Thailand when it comes to visiting the Kingdom. More tourist visas are issued by Thai Embassies than any other visa. The government has over the past 2 years encouraged visitors to obtain a tourist visa before coming to Thailand.