What exactly is an 'aligned pointer'?

Question

Would somebody please tell me what an aligned pointer actually means?

Answer 1

To add to what unwind is explaining, here is a struct I have recently used in an assignment :

struct infosale {               
    int   noseq;                
    char  salesman[30];         
    char  product[11];          
    int   count;                
};                               

You may expect the size of this struct to be (4+30+11+4=) 49 bytes, but it is in fact 52 compared with sizeof. Because noseq is 4 bytes + salesman is 32 bytes (aligned) + product is 12 bytes (aligned) and count is 4 bytes, thus 52 bytes.