1. function Copy(S; Index, Count: Integer): string
e.g. Copy(S1, m, n); this function copies n characters from string S1 starts from mth character and return copied string
2. procedure Delete(var S: string; Index, Count:Integer);
e.g. Delete(S1, m, n), this function deletes n characters from string S1 starts from mth character
3. function Length(S): Integer
e.g. Length('UltraFXP') returns a integer 8