Jargon !:  What are all  those 3 letter names  ?    

The long  answer is SAE.org  names.  over 1000's of names there, and for fun they changed many names in the 1990s just to make all this so much fun.... not.
In the USA we use SAE, standards ,others us ISO.
 (Society of Automotive Engineers long ago set these standards for names in the mid 1980's) Bendix led the way to EFI in the 1950s and was licensed to Bosch.
The first EFI was in Aircraft.  (flyin high there is little air, and tuning AFR on the fly(no pun) is no fun, nor is it easy, enter EFI.
My short answer, is below.  About 30-40 core short names !

Engine Control Names (A primer)    Devices, or Sensors in RED will kill the engine if dead. The ones in Violet color bad tend to force EFI in to Limphome mode.

Sensor
name
Old Alt.
name
Function  Sensor or device.

IAT
---
Air temp, or Intake Air Temperature  sensor. IAT (AFR mixture compensating device)
ECT
WTC/CTS  Engine Coolant Temperature sensor  ECT  Aka; water temperature sensor   300 ohms hot it typical.
MAP
---
Manifold Absolute Pressure.  8V car uses MAP sensor and 16v use MAF.   AKA: BARO
TPS
TP Angle.
Throttle (valve) Position Sensor  TPS  with switch (aka : TP)  does many things but top is fast gas foot enrichment.
O
EGO
Exhaust oxygen sensor  HO2S  , called OXY , OX1 ,OX2,  or Exh. Gas oxy,  lots of names,  all are same.
CMP
CAS
 CAM angle sensor.  CMP in Distributor or end of CAM  1.8L DOHC "Sport" motors- if die, engine DEAD!
CKP
CPS
 Crank position sensor   (96 an newer cars only)  starts dead, but kills accurate timing and misfire detection.
EGR
---
Exhaust Gas Recirculation devices   Lower Nox Emisson (acid rain) and lowers exh valve temperatures greatly.
MIL
CEL /SES
Maintenance Indicated Lamp ,Check Engine Light (SES service engine lamp is  mileage nag lamp)
PCM
ECU/ECM
Power train control module   PCM  EFI controller .  ECM is Engine control module.
MAF
AFS
MASS Air Flow, Sensor  MAF   or AFM/AFS air flow meter or sensor, 16v engines only
ISC
IAC
Idle speed Controller  this is the electric idle control valve.  This operates at all times. 200 times a second.
IAC
CSFI
Idle Air Control  IAC  , this is the Thermostatic only air control, that is open only on a cold engine.
TBI
---
Throttle body fuel injection. On the 8v TBI car, this also contains the only injector. called Single Point Inj.
MPI
---
 Multi Point Injection   16v.  see 4 injectors?, marks this system.  1.6L and 1.8L or bigger.
EVAP
---
Evapoative Emissions  , a system to captures gas tank fumes and burns them up. Difficult to diagnosis.
TCC
---
Torque Converter Clutch (solenoid)  TCC  Lock up Clutch.  Automatic trans,only.
TCM
Tranny brain.
Transmission Control module,  4speed only  ,this brain shifts the transmission. Has its OWN limphome mode.
EGR MAP
---
Used only on some 16v engines and ONLY for EGR testing (OBD2 cars only) Aka: MDP.
VSS
miles per hour sensor.
Vehicle Speed sensors. (Inside the Speedo of most cars, and 1 in Tranny on all 4sp A/T cars)  SPEED SENSOR !
COP
Ignition Coil (DIS)
Coil On Plug or Coil over plug ( spark plugs) 1.8L and up, aka: Distributorless Ignition System.
Wasted Spark , uses 1 coil per two cylinders, and sparks  the pair on the firing TDC and the Exhaust TDC at the same TIME ! (the later fact, is why it's called wasted.)
The EGR is not critical , but engine will not idle, if it sticks open and ECU may invoke Limphome mode,  if it leaks , in any why shape or form, even cracks in ITS casing or its special Gasket.
Most Sidekicks start and run poorly (bad idle) with the MAF/MAP disconnected, but power will be lacking.  "due to MAF /MAP mimic mode known as Limphome or failsafe mode., of the ECU."
Many sensors can be disconnected and the ECU will try to mimic (emulate) them (always poorly) and is for your safety ( you are moving , right?)  All mimics trip off Limphome and about 15MPG ,horrid gas mileage.
List of dis-connectables: (and engine runs) MAF/MAP,TPS,IAT,ECT,CKP, ISC, EVAP, EGR. This trick (fact) can be used to troubleshoot the motor and EFI !   (ISC pulled the motor stalls, so block open throttle a tad and it runs)
If you pull more than one, the motor just floods.. now, or very soon, with black spark plugs ,as a reward. (sorry)
Do not get confused, if the sensor is disconnected and the car runs better, that does not mean it's useless, not at all.    (for sure a mimiced MAF can run better that a dead real MAF)  Use a scan tool and find the truth or a volt  meter.
Case in point , you have huge induction air leaks , say all 4 injectors are particially clogged. and with the MAF wires unplugged, car runs better,  that is because limphome adds huge FUEL, to your false lean motor and helps.
Never assume there is one problem, and plotting all fail modes in a matric + symptoms, is impossibe.  why? you say, because each ECU made works different , at the fine detail (secret) levels...
Rule 2,  if you fool the ECU, it will just do something crazy and dumb  that is what they do. They really are crude hardware sequencers, not intelligent.


MORE:
DLC = Diagnostic Link connector, near battery or near right front headlight shell rear area. (used to command up DTC failures from CEL and to freeze the Ignition timing for setting same) some cars have 2 of them.
DTC = Diagnostic Trouble code (blinking CEL or scan tool data, after 95')  My ECU is thrown DTCs again, we say,  thes just errors discovered by the ECU, and recorded in to memory..
W.O.T = Wide open Throttle.
TPS  Switch, this switch is inside the TPS and signals PCM to enable full Idle controls , if engine is hot. 
The other side of the TPS, is called the TSP POT  Suzuki calls it the TP pin. and is used for Temporary Fuel Enrichment  , wide open throttle detection and rules, throttle cut and cut fuel mode, and other usage !)
CEL = Check engine lamp. aka: Service Engine Soon. SES or to a technician, the MIL lamp.
TB = Throttle Body ( the device that allows a driver of car and right foot,  to control air into the engine, aka: THE ThrottleValve or T.V.)
VSV  = Vacuum Solenoid Valve ( used to operate the EGR, EVAP, Dash Pot)  The engine can have 5 of them.  2 for EGR, 2 or more for EVAP.)
Dash Pot  or D.P. = Device (vacuum acutator) for 8v only , a temporary cold fast idle device ( 3 to 10 seconds delay at start and then it retracts) depending on ambient temperatures this delay time.
CAT =  Catalyst Converter. aka : CATCON. aka; TWC "three-way-Cat" ( a smog filter nothing more) [a missing CAT , kills a good EGR valve or greatly weakens the EGR flow, and you will NOX, HC and CO, in a smog test ]
HC = HydroCarbons , Chem enginer term for wastes raw fuel out the end of tail pipe. NOX, is nasty smog called NitroOxides.  (causes acid rain or worse if breathed)
FPreg. =  Fuel pressure Regulator. 
AFR: = Air fuel Ratio  (ratio of air to fuel , aka: fuel mix) perfect its 14 lbs of air to 1lb of fuel. By mass, not volume.  14lbs of air , is a room 5.6feet cube or 177 cubic feet.   1/6th of one gallon .. So 1/6th gallon to 177 cubic feet of air is perfect AFR. STP.
STP = standard temperature and presssure.  Google that.
EFI = Electronic Fuel Injection,  also called EMS , Engine managment systems. or PCM.
VC = Valve cover. (known for leaking)
OBD = On Board Diagnostics.
PWM = Pulse Width Modulation  ( as used on the injectors and ISC)
JDM = Japan Domestic Market ( cars with no smog controls ( I call them SLICKS) sold to their own country men or to other countries devoid of smog rules.  (89-98?)

A.K.A. = also known as....
HL = head  light ,  , SWB , short wheel base,  or LWB , you guess?
Firewall = that metal wall , keeping burning engine from hopefully non burning occupants! 
LR =left rear , RH- right hand,  RF , LF left front..etc.  used everywhere in books on cars.  (Every one has a right hand, but not all cars drive on the right side, so drivers side usually means, ZERO (with out RHD/LHD known or seen)
LHD= Left hand drive, and RHD  right hand drive cars in UK/ Japan.
CW =clockwise.
CCW = Counter (anti) clockwise.
IFS, Independant Front suspension
IRS, rear.
TDC = Top dead center, and BDC is bottom dead center,  or piston at the top of travel or bottom?  and is also used in the context of firing for TDC. (not exhausting)
BTDC ,means firing  before top dead center. ( used in the context of spark advance, usually or cam timing "valve opens xxx BTDC".) expressed in crank degree's

M/T or MT = Manual transmission,  (see dealer drawings, every page has this. all catalogs ,all books on Suzuki)   A/T = "AT"  Automatic transmission  , most call it A/T but the uFiche and EPC use AT.
Tranny, the transmission, not a transvestite.
IRS,  Internal Revenue Service, RUN !  ok , Independent rear suspension (not on kicks)  Independant Rear Suspension.

Dead stick , oop's wrong business.  for cars I call this , F.O.R.D, found on road Dead.
DIY , Do it your self.
DOA, dead on arrival.
DIW, dead in the water, or F.O.R.D.  found on road dead.
A field KICK ( not foot ball)  you found a kick in the farmers field or in an old barn, Aka, Barn find.  (can be  finders dream come true, if you have cash to get out all the bad fuel)

I will not list them all, I have this here, for fast look up.


Tools:
Scope
DMM  Digtal Mulimeter  (DVM ) a  $3 on sale $4.99 MSRP.

GMM Graphing Mulitmeter  Fluke.

DSO  same but more expensive and Storage ( digital storage o-scope)  The best deal in town.


My contribution to DIY mechs.
rev 6 ++++ 4-12-11 (added MT)