The difference between ‘s and s’ is the former is a possessive form of a noun while the latter is a plural form of the same noun. For example, if we want to denote possession of a car, we use the possessive form ‘s, as in “The car’s engine”. On the other hand, if we want to talk about multiple cars, we use the plural s’, as in “The cars’ engines”. Both possessive and plural forms indicate ownership, but the former is used for single items while the latter is used for multiple items.
The possessive form is also used when referring to someone else’s possession. For example, if we want to talk about a friend’s car, we use the possessive form ‘s, as in “My friend’s car”. In contrast, the plural form is used when referring to multiple people’s items. For example, if we want to talk about the cars of two friends, we use the plural form s’, as in “My friends’ cars”.