Accounting software is rarely used by itself, but sometimes this fact is not considered first. When choosing accounting software for a home or business, it is important to see exactly what other programs the software can interact with, or at least what file formats the program supports. This will make it far easier to place accounting information into a report generator, or to directly import records from a database or other program.
Many applications interact with each other. For example, your operating system interacts with a regular program to get information one it. Also, your anti virus searches your computer for viruses, and will interact with other programs to extract information from them to see if their safe to use. There are so many examples to use, but mainly every program interacts with your operating system in one way or another.
Yes you can have two anti virus programs installed however they may negatively interact with each other and lower the security of your computer instead of raising it. So I would be very carefull what programs you install. However if one program is just a firewall and nothing else. and the other program is just an antivirus program with no firewall then you can definite download both.
A compiler.
An object is a component of a program that knows how to perform certain actions and to interact with other pieces of the program.
A program is software. One program can call another program to be run. Computer systems consist of lots of individual programs which work together. Applications consist of lots of individual programs that work together. So programs need to be able to call other programs. A good example is that a menu can sometimes be one separate program and each option it calls could potentially be other individual programs.
virus
No. Spreadsheet programs do not control or interact directly with the hardware (some DOS ones may have had their own printer drivers). They also do not provide an API for other applications to run on top of them.
There are many hacking programs, but it is illegal to break into someone else's Internet accounts. Plus, hacking programs come with an extra bit of nastiness: malware or viruses for your computer.
A virus is a piece of a program that attaches itself to other programs. In contrast, a worm is a full program that spreads itself, and a trojan is a harmful program that passes itself off as, and in some cases might also be, as useful program.
a program that installes other programs eg. games
The operating system.