This sign is an item of equipment which is ready-to-hand for the driver in his concern with driving, and not for him alone : those who are not travelling with him—and they in particular—also make use of it, either by giving way on the proper side or by stopping. This sign is ready-to-hand within-the-world in the whole equipment-context of vehicles and traffic regulations. It is equipment for indicating, and as equipment, it is constituted by reference or assignment. It has the character of the "in-order-to", its own definite serviceability; it is for indicating.1 This indicating which the sign performs can be taken as a kind of 'referring'. But here we must notice that this 'referring' as indicating is not the ontological structure of the sign as equipment.
Instead, 'referring' as indicating is grounded in the Being-structure of equipment, in serviceability for .... But an entity may have serviceability without thereby becoming a sign. As equipment, a 'hammer' too is constituted by a serviceability, but this does not make it a sign. Indicating, as a 'reference', is a way in which the "towards-which" of a serviceability becomes ontically concrete; it determines an item of equipment as for this "towards-which" [und bestimmt ein Zeug zu diesem]. On the other hand, the kind of reference we get in 'serviceability-for', is an ontologico-categorial attribute of equipment as equipment. That the "towards-which" of serviceability should acquire its concreteness in indicating, is an accident of its equipment-constitution as such. In this example of a sign, the difference between the reference of serviceability and the reference of indicating becomes visible in a rough and ready fashion. These are so far from coinciding that only when they are united does the concreteness of a definite kind of equipment become possible.  Now it is certain that indicating differs in principle from reference as a constitutive state of equipment ; it is just as incontestable that the sign in its turn is related in a peculiar and even distinctive way to the kind of Being which belongs to whatever equipmental totality may be ready-to-hand in the environment, and to its worldly character. In our concernful dealings, equipment for indicating [Zeig-zeug] gets used in a very special way.
1 'Es hat den Charakter des Um-zu, seine bestimmte Dienlichkeit, es ist zum Zeigen. The verb 'dienen', is often followed by an infinitive construction introduced by the preposition 'zu'. Similarly the English 'serve' can be followed by an infinitive in such expressions as 'it serves to indicate ...' In Heidegger's German the 'zu' construction is carried over to the noun 'Dienlichkeit'; the corresponding noun 'serviceability', however, is not normally followed by an infinitive, but rather by an expression introduced by 'for' e.g. 'serviceability for indicating ...' Since the preposition 'zu' plays an important role in this section and the next, it would be desirable to provide a uniform translation for it. We shall, however, translate it as 'for' in such expressions as 'Dienlichkeit zu', but as 'towards' in such expressions as 'Wozu' ('towards-which') and 'Dazu' ('towards-this'), retaining 'in-order-to' for 'Um-zu'.