Control break: A change in the value in a control field between consecutive records in a file.

Advantages: 
1. Provide more information than that of other forms of documentation.
2. The input and output for each module are clearly identified.
3. Can use to determine very easily what modules call the module being examined.

Disadvantages:
1. The main disadvantage of HIPO is that the documentation for a program gets to be rather bulky: there is a page for each module regardless of the actual size of the module.
2. HIPO charts are not as widely used as structure charts and pseudocode.

Sequential search: The sequential search is the most commonly used algorithm for searching an argument table. The search starts with the first table argument and takes each succeeding argument in turn until a match is found.Spaced sequential search: A searching method in which table or index entries at fixed intervals are examined until either the desired entry is found or ti can be determined that the desired entry has been passed over; in the latter case the entries between the last two entries examined are then searched serially.Binary Search: The binary search is a more efficient searching technique for large tables. When the binary search is used, the argument table must be in either ascending or descending order.

Cylinder: The collection of tracks of the same number on a disk, that is, the tracks that can be read from or written to with a single positioning of the accessing mechanism.
Track: One of a series of concentric rings on the surface of a magnetic disk on which data is recorded.
Sector: In computer disk storage, a sector is a subdivision of a track on a magnetic disk or optical disc. Each sector stores a fixed amount of user data.

Top-down programming:
1. The top-down approach has evolved as a useful technique in planning a modular program. 
2. In top-down programming we first define the main program module, which initiates program execution, calls other modules to perform specific functions, and then terminates execution.