D stands for bullet train, G stands for high-speed rail, T stands for express, K stands for air conditioning fast. D, G, Z, K are all trains, just different types of trains.
Naming rules for trains
1. Emu trains (D-prefix)
Emu passenger train (dedicated line) D1001-D9998. \"D\" reads \"move\".
Among them: D1001-D5998 for inter-office, D6001-D9998 for intra-office.
Top speed 250 km\/h. Mainly CRH1, CRH2 and CRH5, the top speed can reach 250 km\/h. The Guangzhou-Shenzhen Line is more full use of this car. The standard pronunciation of railway system is \"move X times\".
2. High-speed rail EMU (G-prefix)
High-speed EMU passenger train (Beijing-Shanghai High-speed Railway) G1001-G9998. \"G\" reads \"high\".
Among them: inter-office G1001-G5998, internal G6001-G9998.
Since December 26, 2009, Wuguang-Guangzhou high-speed rail opened 23 trains, according to regulations, Wuguang-Guangzhou high-speed rail opened high-speed EMU train number with a new letter, \"G\
3. Express Passenger Train (T)
Express passenger train T1-T9998. \"T\" reads \"T\".
The value is T1-T5000 in inter-office and T5001-T9998 in intra-office.
4. Fast passenger train (K-prefix)
Express passenger train (General line) K1-K9998. \"K\" reads \"fast\".
Among them: inter-office K1-K6998, internal K701-K9998.
Extended data
China railway train number rules
China railway train number rules are to distinguish trains in different directions, different types, different sections and different times, and arrange an identification code for each train, that is, the rules of train number. The number of trains is indicated by Arabic numerals, and the number of passenger trains is also added with the initial letter of the Chinese pinyin of the train type before the Arabic numerals.
In order to ensure traffic safety, maintain transportation order and the standardization of train number code, the former Ministry of Railways stipulated that the whole road to Beijing, the branch line to the main line or the designated direction is the upward direction, and the train number is even; On the contrary, the train number is singular in the downward direction.