The fruit can be described as a fertilised egg. After fertilisation, the egg turns into a seed and hatches into a fruit. In some cases, however, the ovary may mature and grow into a fruit without fertilisation; such a thing is called parthenocarpy. Bananas are an excellent example of parthenocarpy fruit. They are not. Therefore, the fruit is called the sterile seed. Fruit is of two kinds: true fruit and false fruit.

Fruit categories:

Fruits are divided into the following three categories, namely:

Simple, Aggregate and Composite.

Simple Fruit: A simple fruit grows from a monocarpellary or monocarpellary ovary of a single flower. In other words, there is only one fruit that grows (separately) in one uterus.Examples- Guava,Brinjal etc.

The simple fruit is also divided into two types, based on the shape of the fruit wall (pericarp).

1. Simply Fleshy (Succulent) Fruits
2. Simple Dry Fruits

Aggregate Fruit: Some fruit grows on a single flower with many different pods; thus, each carpel produces one fruit. As each fruit grows, they combine to form a single structure. Such an aggregate of light fruit is also known as etaerio.Examples- Calotropis,Michelia etc.

Composite or Multiple Fruits: When the whole inflorescence grows into a single fruit, it is a hybrid or mixed fruit. There is a standard envelope for every fruit. Such fruit is also known as infructescence.Examples-Pineapple, Mulberry etc.

True Fruits:

The natural fruit is a ripe or ripe uterus, developed after fertilisation, e.g., Mango, Corn, Grapes, etc.

Some examples of true fruits-

• Mango :In mango the outermost cover or rind is called epiccarp. Edible fleshy part is Mesocarp and the part where the seed is protected is called endocarp. 
• Ber: In ber, Epicarp and Mesocarp both are edible parts while endocarp is drupe.

• Almond and walnut:The rind of Almond and walnut are endocarp and their edible part is seed. 
• Coconut:In coconut Epicarp is hard and thin while Mesocarp is thick and consists of hard fibres. The endocarp is hard and the seed is protected in it. The sweet water and coconut are liquid and solid endosperm.

False or Accessory Fruits: Fruit or pseudo-carp is found in flower parts outside the ovary, e.g., peduncle in cashew-nut, thalamus on apple, pear, gourd, and cucumber; perianth combined in labels and calyx in Dillenia. Jack’s fruit and pineapple are also called false fruits as they grow from all the inflorescences. False fruit is also called pseudocarp or accessory fruit .

Some examples of False or Accessory Fruits are:

• Gaultheria procumbens and Syzygium Jambos derived from Calyx
• Mulberry, pineapple and strawberry found in the Receptacle

Development of fruit :

Pericarp : After ripening, the ovary changes into fruit and  the ovarian wall changes into pericarp. This pericarp may be thick and fleshy or thick and hard or thin and soft.

Pericarp is made up of 3 layers :-

(a)   Outermost layer    =   Epicarp

(b)   Middle layer     =   Mesocarp

(c) Innermost layer  =   Endocarp

         (a) Epicarp – It is the outermost layer. It is thin and hard or soft part. It forms outermost layer of fruit which is also called rind

(b)    Mesocarp : It is the middle layer which is thick and fleshy in mango, peach, date palm. In coconut, this layer is made up of fibres which is also called coir

(c)    Endocarp : It forms the innermost layer it may be thin membrane (eg. Orange, date palm)  or thick and hard (eg. Mango, Coconut)

Some False or Accessory Fruits are:

• Strawberry: Strawberry is an accessory fruit as part of the flesh is found in the subcutaneous hypanthia that contain the ovaries. It is also an example of  aggregate fruit, each fruitlet is an achene. In strawberries, thalamus is fleshy and small achenes are found on its surface.

• Apple: The rind and sponge are made up of thalamus. The main part of the ovary is like cartilage. It means it is hard and dry seeds inside the fruit are present. Eg. Apple, Pear. These are false fruits. Fleshy swollen thalamus of these fruits is edible part.

• Jackfruit: In Jackfruit (Kathal) pistillate flowers are developed around the peduncle. In fruit formation pericarp becomes spongy and fused. Spiny and rough rind is formed by the upper part of the ovaries.
• Pineapple: In Pine apple peduncle bracts and perianth become fleshy. Due to the fusion of perianths of flower a composite fruit is formed. Other growth indicates the flower.
• Mulberry:In mulberry perianth becomes fleshy and the calyx of every flower becomes thick, sweet and fleshy and is edible.

Conclusion:

The fruit can be described as a fertilised egg. After fertilisation, the egg turns into a seed and hatches into a fruit. In some cases, however, the ovary may mature and grow into a fruit without fertilisation; such a thing is called parthenocarpy. Bananas are an excellent example of parthenocarpy fruit. They are not. Therefore, the fruit is called the sterile seed. Fruit is of two kinds: true fruit and false fruit.