Now your friends can safely unzip it into their program files or user directory and run your program.
If you are unsure what your program's dependencies are, check out one of: http://www.dependencywalker.com/ (fancy, GUI program) http://www.wheaty.net/pedump.zip (simple command-line program)
You can typically ignore dependencies found in your C:/Windows/system32/ and C:/Windows/SysWOW64/ directories.
Ok lets make it super simple. Say i have a command line program that just outputs a single line of text. how would i send this to my friend and make it so he can run the program.
When you finish writing the code, you compile it.
Than go to the folder where your compiler saves the program.
And there you will need the file that has the .exe extension.
Also you will need the dependencies mentioned by Duoas for .exe to work.
Put them in a folder, zip them and send to your friend.