To determine whether the job can be done with a commercial software package, you need to be aware of the   different   software   packages   available   and   their capabilities  and  features.    If it appears you can use a commercial  software  package  and  your  AIS  facility does not have it, start looking at the different govern- ment  contracts  in  effect  to  locate  the  particular  software package  you  are  interested  in.  If  the  software  is  not available on contract, you will have to look for outside sources.  Once  you  locate  the  software  package  and obtain approval for purchase, you can start the process of filling out the paperwork to order the software. If   you   determine   no   commercial   software   is available to accomplish the user’s request, you need to look at the expertise available in your AIS facility and what  programming  software  is  available  at  your  facility to  accomplish  the  job.  Powerful  software  is  available  to mike  the  programmer’s  work  easier.  This  software  falls into one or more of the following categories: Query  languages.  Allow records to be printed or displayed in a specified format. Database  languages.  Allow records to be added or  retrieved  and  manipulated  following  set formats. Report generators. Allow reports to be created from retrieved data records. Application  generators.  Allow the use of pre- written modules in creating a program. High-level  languages.  Allow  the  programmer to create a program from scratch. Generalized  software.  Directs  certain  internal computer functions. Determine System Hardware Requirements Once  you  determine  the  source  of  the  program, whether  a  commercial  or  an  in-house  program,  you need to look at what type of hardware will be required. Commercial   software   will   have   the   hardware requirements  stated  in  the  paperwork.  The  users  may have  certain  hardware  requirements  dictated  to  them that will have to be met. For example, a laser printer, a specific type of floppy drive, or a CD-ROM drive may be  required.  For  in-house  programs,  it  may  be  more difficult  to  determine  the  hardware  needed  until  the program specifications are complete. When additional hardware is required, you should first determine if it is available at the facility. You may find the hardware needed is not being used where it is located  and  you  can  move  it  to  meet  the  new requirements.    If  the  hardware  is  not  available  at  the facility, begin the acquisition process. This process is the  same  as  for  software,  except,  in  most  cases,  the requirements  will  have  to  go  out  on  bids  to  several companies. With this process, it may take a long time to receive the hardware. You should plan accordingly. Calculate Memory Requirements When  translating  user  requirements  into  an application, there are several things to keep in mind. We have   covered   the   system   software   and   hardware requirements; now, we turn our attention to the memory requirements. Calculate   the   memory   requirements carefully; it will do no one any good to create a program that can not be run due to memory constraints of the system.   Factors   to   be   combined   when   calculating memory requirements are: .  the  operating  system, l  the  program,  and . the data to be input. By taking into consideration the memory requirements of each of these factors, there should be no problems (as far as memory goes) with running the programs. I/O  AND  PROGRAM  SPECIFICATIONS DEVELOPMENT Once you develop the pseudocode and identify the software  and  hardware  requirements,  you  can  begin developing the I/O and program specifications. This is also a good time to determine what type of file organiza- tion  method  will  best  suit  the  application.  The  I/O specifications   will   require   the   users   interaction   to further detail what they need as input data and output material. They are your primary source for this infor- mation.  To  prepare  the  program  specifications,  you  will use the pseudocode and design the program to match. Also, look at the memory and storage requirements for the  program.  You  may  have  to  adjust  the  hardware requirements to match the program specifications. Be sure you are not going to overload the computer system. File Organization File  organization  is  the  technique  of  physically arranging the records of a file on a storage media. When the programmer creates a subschema, a determination must be made on how the file will be accessed by the program.  The  three  file  organizations  methods  used are: sequential, indexed sequential, and direct. 3-20