An open-source software refers to that computer software where the source is open- meaning, the general public can easily access it and then use it. It is generally referred to as OSS, and the source code of an OSS is public. It makes use of the code that is available on the internet for free. Examples include Firefox, Gimp, OpenOffice, Android, Alfresco, Thunderbird, etc. On the other hand, a closed source software refers to that type of computer software in which the source code remains closed- meaning, the public doesn’t have access to its source code. It is generally referred to as CSS, and the source is protected in it. Thus, only the organisation/individual who has created this code has access to it for making any changes. Examples include Google Earth, Skype, Adobe Flash, Java, Adobe Reader, Virtual Box, WinRAR, Microsoft Windows, and many more.