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This calculator is quite powerful. It has a two-line display, an alphanumeric part where expressions are entered, and a numeric part of 10+2 digits for the results. Expressions can be edited and "replayed". The calculator has statistical functions and can perform calculations in different base systems. Integrals can be calculated numerically, typing ∫(sin x, 0, π) for instance gives the result 2.
This calculator (as do many other CASIO scientific calculators) uses one and the same key for both the constant π as well as exponents. This works as follows. When you first enter digits, the "EXP"-key will enable you to enter the numbers exponent, otherwise it will enter the constant π.
This calculator has a two-line display, one that shows the formula entered, and the other which shows the results. To perform operations on a previous result, the "Ans"-key has to be used. This method is rather cumbersome in some cases. Especially when you're used to "normal" scientific calculators where, to calculate the root of a result one simply taps the appropriate key. On this calculator, one has to type "√" "Ans" "Exe". CASIO has perfected the two-line calculation method later on with the CASIO fx-82TL.
What I don't like are the dark display and its three shift modes.
A very nice feature is a storage compartment for a spare battery. Inside the case there's room to put a spare battery. Are there any other calculators with this feature?
Overall, nice, useful and conveniently small.