how do i get flashcart? Explain all please. what is a flashcart how does it work

i posted earlier and i would really like to put the downloads onto my ds i will buy in the future, but im knowledge thirsty and would like to know everything now hehe.List of questains:-Will it work better (who cares really)? (just wondering since ds emulation ain't perfect)
-what is a flash cart, how do i get one?
-how do i put it on the ds?
-will i need to use the emulator on the ds (ya lame, but it might be true.)?:'( help every second that goes buy i get more mature and will have less brain capacity! ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???im i missing a questain, just include it anyway! HELP!!!!!!

Well yeah in most cases it will work better (features etc.) You can buy a flashcart from a online store etc. See GBAtemp.net. Just buy it, install firmware, and then put it in your DS like a regular cartridge. You don't have to use emulators, they're only for other systems that can be emulated on the DS.