With closed source software (also known as proprietary software), the public is not given access to the source code, so they can’t see or modify it in any way. But with open source software, the source code is publicly available to anyone who wants it, and programmers can read or change that code if they desire.
Source:
https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://edu.gcfglobal.org/en/basic-computer-skills/open-source-vs-closed-source-software/1/%23:~:text%3DWith%2520closed%2520source%2520software%2520(also,that%2520code%2520if%2520they%2520desire.&ved=2ahUKEwif4oGDp6iIAxXWklYBHZ1SONgQFnoECF0QBQ&sqi=2&usg=AOvVaw079kOjvFm2gsyYO_GxeZMq