files and their organization learning objective in this we will discuss the basic attributes of file and the different ways in which files can be organized in the secondary memory thenwe will learn about different indexing strategies that allow efficient and faster access to these files introduction nowadaysmost organizations use data collection applications which collect large amounts of data in one form or other for examplewhen we seek admission in collegea lot of data such as our nameaddressphone numberthe course in which we want to seek admissionaggregate of marks obtained in the last examinationand so onare collected similarlyto open bank accountwe need to provide lot of input all these data were traditionally stored on paper documentsbut handling these documents had always been chaotic and difficult task similarlyscientific experiments and satellites also generate enormous amounts of data thereforein order to efficiently analyse all the data that has been collected from different sourcesit has become necessity to store the data in computers in the form of files in computer terminologya file is block of useful data which is available to computer program and is usually stored on persistent storage medium storing file on persistent storage medium like hard disk ensures the availability of the file for future use these daysfiles stored on computers are good alternative to paper documents that were once stored in offices and libraries data hierarchy every file contains data which can be organized in hierarchy to present systematic organization the data hierarchy includes data items such as fieldsrecordsfilesand database these terms are defined below