Some special abbreviations in my web pages are made up on the fly. For instance, in an early paragraph of a tech article I might refer to Lighting Switch or Brake Switch (capitalization as a proper name of a device). Then later in the same tech article I might use LS or BS for the same device reference. In other words, the abbreviation is "Defined Elsewhere On The Page". I do use such abbreviations in electrical schematics, but the use is usually obvious depending on what is connected. Following is a list of abbreviations you may find in the electrical diagrams.

B    = Blower (heater control fan switch knob)
BS   = Brake Switch
CB   = Control Box
E    = Earth (ground connection)
E, 1/4, 1/2, 3/4, F = Fuel gauge markings
EC   = Engine Compartment
F    = Fog light (switch knob)
G    = Ground (same as Earth)
GRD  = Ground (same as Earth)
H2O  = Water
HB   = High Beam
HL   = Head light
I    = Ignition (ignition switch knob)
L    = Lighting (light switch)
LB   = Low Beam (sometimes Light Bulb)
LH   = Left Hand
Light= illumination that you can see (any color)
Lamp = a lighting fixture assembly (or a bulb)
Lamp = Portable lighting device (flash light, torch)
M    = Map (map light knob)
M    = Motor (wipers or heater)
OFF  = Off
ON   = On
P    = Panel (panel light dimmer switch knob)
RH   = Right Hand
TL   = Tail Light
TS   = Turn Signal or Turn Switch
W    = Wipers (wiper switch knob)

Common terminal designations on electrical devices:
+ or -   = Battery terminal reference for device polarity.
1, 2, E  =  Terminals an wiper motor
1, 2, 3, 4, 5, 6, 7, 8 - Terminals on the TS relay unit
A, A1    = Primary power (battery) on control box or lighting switch
A1, A2, A3, A4 = Fuse box connections
B or BAT = Battery (fuel gauge, flasher unit)
CB       = Contact Breaker (ignition coil or distributor)
D        = Dynamo on control box and generator
E        = Earth (electrical ground anywhere)
F        = Field (control box and generator)
F        = Flasher or Fuse (turn signal switch input terminal)
FP       = Fuel Pump
I or IGN = Ignition
L        = Left (or Lamp)
P        = Pilot (as in pilot lamp, indicator light, flasher unit)
R        = Right
S1, S2   = Lighting switch terminals
SW       = Switch (ignition coil)
T        = Tank (fuel gauge)

Primary Wire Color Codes:
B  = Black
G  = Green
N  = browN
P  = Purple
R  = Red
U  = blUe
W  = White
Y  = Yellow