• A simple letter L stands for an in-city bus Line for it is the most fundamental transport way.
  
• In this guide, *CT* means the abbreviation of the city name that the line serves for. # means single or multiple number(s) in order, it can be passed if there is only one bus line in the city.
  
• e.g., L SH 1 stands for the first in-city bus line in Shanghai (or any other city might be called as SH). L NB 14 stands for the 14th in-city bus line in Ningbo (or might be Nuremberg). L HZ stands for the only bus line in Hangzhou.

In-city bus stops are usually suggested to leave spacing of no less than 400m (about 4 AI-building blocks) between each other.
Intercity bus has a separate letter.

• A letter G stands for a truck line for it transports Goods and carGo.
  
• *CT* means the abbreviation of the city name that the industry chain finally serves for. *Cargo* means the cargo that the line transports. # means single or multiple number(s) in order, it can be passed if there is only one truck line supplying the cargo for the factory or the city.
  
• e.g., G SH Tool 2 stands for the second truck line supplying tools for Shanghai.

• BRT is a kind of bus indeed. A bus line has longer average stop spacing than regular one or connects important sites such as traffic hubs, tourist attractions or remote positions including different towns is usually called bus rapid transit (BRT). Thus, in TPF2, BRT usually equals to intercity bus line, and it is usually simpler to use BRT to indicate the concept.

BRT Lines sometimes utilize viaducts and specific bus lanes.
BRT Lines are usually suggested to share 1~3 stops with connecting in-city bus lines in order of easy bus transiting besides causing too much traffic jam in cities.

• As bus lines do, the only in-city tram line of its city passes # and an intercity tram line passes *CT* in numbering.
  
• e.g., T1, T SH 9.

A tram line in TPF2 is usually upgraded from a bus line including in-city and intercity lines. Therefore, all planning suggestions for bus lines are adaptable for tram lines as well.

• A letter R stands for a Regular train line for it is the most fundamental Railway transport form.
  
• A passenger train line passes *CT* *Cargo* and a cargo train line passes # if there is only one truck line supplying the cargo for the factory or the city.
  
• e.g., R9, R NB Food 2.

A regular train usually stop once for every town. In the case that the neighboring towns space too far, using highspeed train and constructing highspeed railway partly are recommended.
Suburban train and highspeed train have separate letters.

A suburban train usually stops once for a small town and twice for a large town but rarely stops three or even more times for one town. When stops twice for a large town, the two stations are supposed to locate at different sides of the town.
Suburban line uses common train and railway.

A highspeed train usually stops only once for a large town and dose not stops for a small town. It is sometimes even necessary to build a new station for reducing curving the highspeed line too much.
A highspeed train requires highspeed railway.

• Though a train line can be regular, suburban or of highspeed as referred, there is no natural difference among them. The standard of catalogizing should be flexible.
  
• e.g., R5 could be S14 after adding several stations or H8 after cancelling several stations.

Only usable in marine. There are no specific principles for terrain-oriented transit ways, but it is recommended to build a bridge and run a bus, truck, or tram line when the path length of marine is less than 400m (about 4 AI-building blocks) between ports.

An airline is of extremely expensive purchasing and maintenance cost. It is recommended to leave spacing of no less than 12,000m between airports.

A small letter following the origin line number is applied to express a branch, clockwise / counterclockwise of a circuit or any other varieties of a line. e.g., T19a, T19b, Q2x.