data typesor adts we'll describe what this means in "linked lists "overview of algorithms many of the algorithms we'll discuss apply directly to specific data structures for most data structuresyou need to know how to insert new data item search for specified item delete specified item you may also need to know how to iterate through all the items in data structurevisiting each one in turn so as to display it or perform some other action on it one important algorithm category is sorting there are many ways to sort dataand we devote "simple sorting,and "advanced sorting,to these algorithms the concept of recursion is important in designing certain algorithms recursion involves method ( functioncalling itself we'll look at recursion in "recursion definitions let' look at few of the terms that we'll be using throughout this book database we'll use the term database to refer to all the data that will be dealt with in particular situation we'll assume that each item in database has similar format as an exampleif you create an address book using the cardfile programall the cards you've created constitute database the term file is sometimes used in this sensebut because our database is often stored in the computer' memory rather than on diskthis term can be misleading the term database can also refer to large program consisting of many data structures and algorithmswhich relate to each other in complex ways howeverwe'll restrict our use of the term to the more modest definition record records are the units into which database is divided they provide format for storing information in the cardfile programeach card represents record record includes all the information about some entityin situation in which there are many such entities record might correspond to person in personnel filea car part in an auto supply inventoryor recipe in cookbook file field record is usually divided into several fields field holds particular kind of data in the cardfile program there are really only two fieldsthe index line (above the double line