Use of external code sources

Question 1

What is an external code source?

Answer 1

A unit (e.g. module, package or library) of code written by developers and released or sold for use by others. Examples include libraries for developing graphical user interfaces, javascript libraries, web development frameworks.

Question 2

Why can external code sources be useful?

Answer 2

You shouldn’t reinvent the wheel if something already exists. Software is likely to be well tested if used by lots of other people