Difference between Bug and Error

Bug
If the software does not meet the below criteria then it is bug

  • Any thing which is not defined by the client
  • If Excess Things are added in the software
  • Software does not produce a expected result
  • it is not user friendly

Error
An Error is a programming mistake, if the function is not responding with expected result then it is error, Bug is any thing which is not added or excess added in to software or it is functionally not well defined and it is not user friendly software. Then errors are also comes under bug

Some Major Computer System Failures Caused by Bugs

1. In August of 2006 a U.S. government student loan service erroneously made public the personal data of as many as 21,000 borrowers on it’s web site, due to a software error. The bug was fixed and the government department subsequently offered to arrange for free credit monitoring services for those affected
2. A September 2006 news report indicated problems with software utilized in a state government’s primary election, resulting in periodic unexpected rebooting of voter checking machines, which were separate from the electronic voting machines, and resulted in confusion and delays at voting sites. The problem was reportedly due to insufficient testing
3. Software bugs in a Soviet early-warning monitoring system nearly brought on nuclear war in 1983, according to news reports in early 1999. The software was supposed to filter out false missile detections caused by Soviet satellites picking up sunlight reflections off cloud-tops, but failed to do so. Disaster was averted when a Soviet commander, based on what he said was a ‘…funny feeling in my gut’, decided the apparent missile attack was a false alarm. The filtering software code was rewritten