What’s the difference between System.String and System.StringBuilder classes?

sytem.string is immutable it means if we r performing
string manipulations new memory is allocated each time
eg:string a=dev; a=arora; in this case new memory is
created a=arora and previously a=dev wil be deleted.so
major impact on performance but string builder is mutable
so same memory wil be updated for the same so good
performance.

String..
1.Its a class used to handle strings.
2.Here concatenation is used to combine two strings.
3.String object is used to concatenate two strings.
4.The first string is combined to the other string by
creating a new copy in the memory as a string object, and
then the old
string is deleted
5.we say "Strings are immutable".

String Builder..
1.This is also the class used to handle strings.
2.Here Append method is used.
3.Here, String builder object is used.
4.Insertion is done on the existing string.
5.Usage of String Builder is more efficient in case large
amounts of string manipulations have to be performed