Tarkvaratehnika
- The system requirements are likely to change while the system is being
developed because the environment is changing. Therefore a delivered system
won't meet its requirements!
- Systems are tightly coupled with their environment. When a system is installed
in an environment it changes that environment and therefore changes the
system requirements.
- Systems MUST be changed if they are to remain useful in an environment.
LEHMAN'S LAWS (MA EI TEA KAS NEID PEAB PÄHE AJAJAMA, AGA SIIN
NAD ON)
Software maintenance
- Modifying a program after it has been put into use.
- The term is mostly used for changing custom software. Generic software
products are said to evolve to create new versions.
- Maintenance does not normally involve major changes to the system's
architecture.
- Changes are implemented by modifying existing components and adding new
components to the system.
Types of maintenance
- Maintenance to repair software faults
annaabi.ee 
