When it comes to human inventions, almost everything has a purpose. However, there are small and big things that we interact with on a daily basis but never know what purpose they serve. Many will shock you and others will make you laugh. Here are 10 common things you never knew about their purpose.
Notebook margins
We have all started writing on books with two red lines running on either side of the page. Even though margins have been used to take extra notes or even feedback from teachers, that is not their intended purpose.
In the past, books were victims of rats that gnawed on their edges and the lines were placed there to ensure you never start writing on parts that would be breakfast for the rats.
Holes in padlocks