Compare arrays, and returns the differences (compare values only, using a user-defined key comparison function) array_udiff_assoc() Compare arrays, and returns the differences (compare keys and values, using a built-in function to compare the keys and a user-defined function to compare the values) array_udiff_uassoc() Compare arrays, and returns the differences (compare keys and values, using two user-defined key comparison functions)
Instagram usage is particularly strong among millennials. This year, there will be 48.2 million millennial Instagram users in the US. By 2019, nearly two-thirds of all millennial smartphone users will use Instagram.
Twitter and Instagram resonate with urbanites and younger adults, and non-whites. (Facebook has over 70% usage among whites, Hispanics and black users, Pew notes.) All of them, excepting LinkedIn, has its highest proportion of users in the 18-29 age bracket; LinkedIn is more popular with the 30-49 group.