Open source is denoting software for which the original source code is made freely available and may be redistributed and modified. People tend to use this code and just rewrite something more simpler and easier to use. This is done so by altering the code by just one bit from the orginal one because it doesn’t require much change. Some changes like sprite changes to the code will allow it to be looking different.
When something is open source everybody has access to it and is allowed to change it whatever way they want. This way they will be able to re-distribute the product after changing it by a bit since it can be gotten off the internet. Products like these are similar alike to other products out there because people tend to just change a portion of the code and say it is theirs. This is wrong overall due to everybody being able to do the same thing without working or writing the program.