say just for a learning experience i wanted to make my own class that would create strings.

Could someone let me know how exactly the string class works. I mean how does it take a character and put it in memory and then how does it keep up w/ all the different characters and put them into a string.

I know that there is already a string.h file out there but say i wanted to create my own file for creating a string from characters. how would i need to go about it? WHere would i need to start?