What we call as a flower of Daisy ( Singular ) is in fact a collection of numerous tiny flowers ( To put emphasis on their tiny structure they are technically called 'florets' ).
There are two distinct types of florets
1) Peripheral 'Ray Florets'= white in color and look like petals of an ordinary flower .
2 ) The central "Disc Florets " = They look like stamens and carpels of an ordinary flower.
The part that you are referring to is The Disc.
In the photo on the link below you can see the peripheral 'Ray Florets ' that are white in color and at the center the Disc that is all covered with 'Disc Florets' that are yellowish brown in color .
In the link below you can see a single ' Ray Floret ' It is tiny .Still a flower in its own right !!!
In the link below you will be able to see a ' Disc floret ' of the same !
Now see both of them together for comparison==
What is the yellow part in the center of a daisy called?
here you are
Reply:Those are called disc flowers. The white "petals" are called ray flowers.
What most people believe are petals are actually parts of individual flowers in an inflourescence of flowers.
This is kind of confusing and difficult to explain in writing. Sorry if this was confusing.
Reply:I believe it's called the eye.
hope this helps!