Bangkok, known to Thais as "Krung Thep" which means City of Angels was established in 1782 by King Rama I as the capital of Siam. Like other modern cities in the world, Bangkok has many skyscrapers, luxurious hotels, high-tech shopping malls and a modern international airport. However, Bangkok has managed to retain its traditional charm. It's a mixture of old and new, of East and West and this is apparent wherever you go in this intriguing city.
Bangkok is the usual gateway for most travellers, and you should plan on three to five days in the capital. This allows sufficient time for seeing the major sights, taking perhaps on out-of town day excursion (Ayuthaya or Kanchaburi are top choices), and exploring Bangkok's dinning and shopping possibility. For a different scene, Northern Thailand affords plenty of scope for both cultural sight seeing and refreshing escapes into the country side. Chiangmai is the best base for exploring the region, offering it's own sights as well as numerous excursion options and stay of four or five days give a good introduction. If you have more time, overnight visits to Mae Hongson or Chiangrai are well worthwhile.
If beach vacation is your priority, Bangkok could be followed by a week at Phuket or Samui Island, which offer the most exotic settings. Should you time be limited, the resorts of Pattaya, Rayong, Cha Am and Hua Hin are closer to the capital.
The variations for a visit to Thailand are near endless, and perhaps the best advise to bear in mind when arranging your trip is to plan coming back.