hfe classifications in data sheets
Let's dissect the word 2SC828A...


  2


This is part of the Japanese Industrial Standard where they denote the markings of transistors with 2SC, 2SA and more. The "2" like you said means it's a transistor (where "1" means diode).




  SC


Again part of the JIS, the "SC" stands for NPN high frequency transistor.




  828


So far I am unable to tell a pattern between the 3 numbers and the other characteristics. All I know is that if the number is different from another 2SC transistor, some characteristics would vary.




  A


The A in 2SC828A denotes the voltage rating of the transistor. Generally, higher values like B and C have higher voltage ratings. Like the TIP35C.



But wait... There is an extra letter that will show up on your transistor. So your transistor will actually say something like, 2SC828AQ, 2SC828AR or 2SC828AS, being 3 variants of 2SC828A. This explains your question with the Q/R/S part of the hFE shown in your datasheet.

The suffix your transistor has determines which hFE gain it will have, as concluded from the datasheet.


Q in 2SC828AQ has a hFE of 130-260.
R in 2SC828AR has a hFE of 180-360.
S in 2SC828AS has a hFE of 260-520.


These suffix letters are also Hfe ranks. See here.



Source: http://www.transparentsound.com/transistors/vintage-transistors/JIS/jis01.htm