Buddy systems: A method of handling the storage management problem is kept individual free lists for blocks of dissimilar sizes. Every list having free blocks of only one particular size. For example, memory having 1024 words then it may be divided into fifteen blocks, one block of 256 words, t blocks of 128 words, four blocks of 64 words, and 8 blocks of 32 words. Whenever sport is requested the least block is whose size is greater than or equal to the size required to reserve for example a block of 97 words is field by a block of size of 128 but in this method there are various limitation, first, space is wasted because of internal fragmentation, second, a request of block size 300 cannot be filled. The largest size is maintained is 256, the source of this problem is that free space is never combined