What is ta'aruf and how is it different from dating or being a 'couple'?

Ta'aruf is the process of getting to know each other for the purpose of marriage within the limits of the Shariah, while being a 'couple' is usually a romantic relationship without commitment or limits.
Ta'aruf has a clear aim (marriage), involves the wali or an intermediary, takes place over a reasonable period, and is conducted without khalwat, touching or flirtatious conversation. It usually begins with an exchange of biodata, followed by chaperoned meetings, discussion of life values, and istikharah. Dating, by contrast, often involves being alone together and intimacy that comes close to zina, whereas Allah says "do not come near zina". A good ta'aruf does not necessarily end in marriage; if the two are not compatible, it is ended kindly. See criteria for choosing a spouse.