Some basic facts on Bugs

Just felt like I should start out the first serious post giving an explanation on what exactly a bug is.


First of a bug is defined by Wikipedia as "an error, flaw, failure, or fault in a computer system or program that causes it to produce an incorrect or unexpected result." There are many kinds of bugs, and they can have varying effects from minor grammar errors, to big bugs that can crash computers and cost tons of money or even lives.  A recent example of a major bug was last year when the affordable care act was implemented here in the US and the website that was built came across all sorts of problems due to inadequate testing.  This is of course why software testing is seen as an essential job.


Errors are usually the most common type of bug, and are created by either the developers, or by a user entering an incorrect value in the software.  It can be easy to remember this by remembering the phrase 'human error'.


Failures, and faults are bugs that are caused by the software itself.


Wikipedia defined failures and faults as "A fault is defined as an abnormal condition or defect at the component, equipment, or sub-system level which may lead to a failure." while "A Failure is the state or condition of not meeting a desirable or intended objective."  Basically failures are caused by faults or defects in the system.


Lastly the term 'bug' has apparently been used for over a century to describe mechanical or engineering problems.  But when I first started out learning about software bugs I heard that the first computer bug was discovered at Harvard in the late 1940's when computers were giant things that took up entire rooms, and it was a moth that got into the computer.  It was a literal 'bug' in the system which is kind of funny, and a lot easier to fix.


Below is a link to an image of this legendary first bug.


http://en.wikipedia.org/wiki/Software_bug#mediaviewer/File:H96566k.jpg