What are karate belt colors in sequence?

in brief 
karate belt colours ..9th Kyu - white
8th Kyu - yellow
7th Kyu - orange
6th Kyu - green
5th Kyu - blue
4th Kyu - purple
3rd Kyu - brown
2nd Kyu - brown 2
1st Kyu - brown 3
1st Dan onward - black


Detailed:
If it's traditional Karate there should be 9 Kyu grades before Dan (black belt) grades (Kyu means 9 in Japanese). Although different styles and Dojos will have variation in both grading and syllabus requirements.

The Dojo at which I currently study follows the traditional WadoRyu Karate syllabuses. Junior (below 14 years old) follow the "mon" grading system and adults follow the "Kyu" grading system.

Our Kyu Grading structure is:

Beginner Grades
9th White Belt (Red Tag/Red Stripe)
8th White Belt (Black Tag)
7th Yellow Belt
6th Orange Belt
5th Green Belt

Sempai Grades
4th Blue Belt
3rd Purple Belt
2nd Brown Belt
1st Brown Belt (Black Tag)

Advanced Grades (Black Belt)
1st Dan - Minimum Age 16 years & Held 1st Kyu for 1 year.
2nd Dan - Minimum Age19 years and trained while holding 1st dan for 2years
3rd Dan - Minimum Age 22 years and trained while holding 2nd dan for 3years