A flower by any other name is still just a flower. Yes, this is true but that does not always apply to fragrances. Perfumes and colognes are different when it comes down to the technical terminology. An eau de toilette is not the same as a perfume or an eau de parfum.
Many people make that mistake when buying and it later can give them a bit of trouble. You cannot expect or count on the sales clerk to know the differences either. It is not his or her job to make sure you are an informed customer. That is your job. With a little bit of reading you will know the facts.
There are three bottles standing on a department store counter arranged according to size. The tallest one is called an eau de toilette. It is often confused with being a perfume when in fact it is more like a body splash or similar in scent to a body lotion.
The second biggest is the eau de parfum. The third bottle is quite a bit smaller than the other two and is a perfume. Now, on to the subtle, or not so fragrantly subtle, differences.
The toilette water is a less concentrated fragrance that typically contains 1-6% concentration of perfume. It is meant to be a light and short lasting fragrance, typically like a body splash or spray mist that is found in after-shower products and also found in body lotion products. The second bottle, the eau de parfum, is the most common type of fragrance.
It is more expensive than the toilette water and contains typically 7-15% perfume concentrate. The third and much smaller bottle is the actual perfume itself. It is also known as extract or extrait perfume and is 15-40% concentrate. It is the most expensive version of the three and lasts the longest, and is typically used with an atomizer and/or used very lightly on pulse points to minimize the overwhelming impact they can have on the senses.
So there you go. You can now differentiate between the three types of "perfumes" that are on the market today. There is the eau de toilette, the eau de parfum and the actual, usually expensive, perfume. You should now be able to go to that fragrance counter and get exactly what you want without worrying about the differences between the three and why the smaller bottles cost so much more.