EF
The chassis code for the 88-91
civic/crx models in Japan. Some people like to refer to all 88-91 as EFs though.
ED
The chassis code for the 88-91 civic models in the United States.
EE
The chassis code for the 88-91 crx models in the United States.
Fourth Generation/4th Gen
Refers to the number of body styles the Civic has gone through. The 88-91 Civic is the Fourth Generation Civic.
JDM (Japanese Domestic Market)
It refers to
cars with specifications for the Japanese Domestic Markets. JDM Sis had DOHC ZC engines, Si-Rs had B16As.
EDM (European Domestic Market)
It refers to cars with specifications for the European Domestic Markets.
USDM (United States Domestic Market)
It refers to cars with specifications for the United States Domestic Markets.
STD (USDM) / 70hp / D15B1 / "Standard"
The most basic Civic Hatchback. 4 Speed Manual Transmission, no luxury features.
DX (USDM) / 92hp / D15B2 / "Deluxe"
The mid-level of Civic Hatchback. 5 Speed Manual available and 4 Speed Automatic, some luxury features, but still basic.
Si (USDM) / 108hp / D16A6 / "Sport Injection"
The highest grade of Civic Hatchback in America, only available in 5 Speed Manual, most power and performance, with all luxury features avilable.
Si (JDM) / 137hp / (DOHC) ZC / "Sport Injection"
The 2nd highest grade of Civic Hatchback in Japan, more power and performance over base models.
Si-R (JDM) / 160hp / B16A(1) / "Sport Injection-Racing"
The highest grade of Civic Hatchback in Japan, most power and performance, came with different front end than other models.