How is?External. Sorry.Contagious.Mein file allocation method causes fragmentation like that understood like it is a contagious block and then files have to be stored in it. So external fragmentation could be cost. But I didn't understand this thing like.How the linked and the index one?Are preventing it. Why? What is special in them that they are not causing external fragmentation because in that also in linked also.The scattered memory is allocated differentially like at different places in language this way and then pointers are attached to it. Then how it is preventing external fragmentation and that also it could be a case that a larger memory comes and the smaller blocks are there so nothing. So no memory is there to satisfy the needs of that larger continuous.Process. It could be in that way also.Mahajan LinkedIn index methods are preventing the external fragmentation.