Canon Elph Sd980is

Difference between SD and SDHC flash cards for Canon Ixus SD980is?

I just bought the Canon ELPH camera and said he must SD980is SD or SDHC card. What is the difference between the two? Also, seeing some of the SD cards on Amazon, they say they are class 4, class 2, etc. What that mean?

SDHC high capacity SD card. Maximum capacity of SD card is 2GB, while SDHC cards are supplied with 4-32 GB Class 2, Class 4 and class 6 means at least two data transfer cases, 4 and 6 MB per second, so if you want a quick transfer of class 6 is the best. % Http: / / www.amazon.com/gp/redirect.html?ie=UTF8&location=http 3A% 2F% 2Fs 2Fwww.amazon.com 3DUTF8 3Fie %%%%%%% 3Dtrue 26ref_ 26redirect 3Dsr 255Fnr% 255F0% 255Fn%%%%% 26keywords 3Dsd 2520card 26qid 26bbn 3D493964%%%%% 3D1264651887 26rnid 3D493964% 26rh% 3DN% 253A172282% 252Ck 253Asd%%% 2520card 252Cn% 253A% 2521493964%% 253A502394 252Cn and tag = computer0bd-20 and linkCode = UR2 and camping = 390957 1789 = Creative

Testing Touch AF tracking on Canon SD980IS