Usually that is the intention, but Holland is also a region INSIDE the Netherlands.If someone says Holland or the Netherlands referring to countries, they mean the same thing. But for a specific geographic term, it may mean a smaller area. The Netherlands have 12 regions/provinces including North-Holland (Noord-Holland) and South-Holland (Zuid-Holland). Since the capital Amsterdam is in North-Holland many people refer to the Netherlands as Holland. Dutch people dont mind - in fact its used a lot by them. Its just easier.
Netherlands is the English translation of Nederland. Nederland literally means low lying land (Neder is an older word with the definition low and land means land). The Netherlands are partially located below sea level and that is the reason why it is called The Netherlands.In English and multiple other languages the country has been given the plural form, since you could say that The Nederlands exists of multiple low lying lands. This was also the case till 1815. Before that The Netherlands as a whole didnt exist.In other languages you can also see this translation of low lying lands. For example in French: les Pays-Bas, in German: die Niederlande and in Italian: Paesi Bassi.