These are the services of cloud actually cloud is something which will provide you facilities even if you don't have the resources. As for example you need storage bt you don't have sdcard or hard disk cloud will provide you space or memory bt you will not gonna get it physically it is staas storage as a service .
Iaas is a infrastructure as a service suppose you want to use a operating system bt you don't want to get it install in your system then in that case you can use infrastructure as a service or IAAS
PAAS examples of paas is very common nowadays when we use a online compiler for a code it is a type of paas . In this we don't have the compiler with us in our system it doesnot uses our memory bt we can do programming very well in this
Next is saas software as a service as the name suggest it will provide us the software access . As for example your system doesn't have Firefox bt your friends system have and you are using your friends Firefox from your system it is the example of saas.
One more is there which is not that much popular gaas game as a service

Dear rashi,

These are the various types of cloud available so if you want to learn more about it go through the link below.

https://www.chargebee.com/blog/understanding-types-cloud-computing/

IAAS PAAS and SAAS are three types of services in cloud.

IAAS is Infrastructure as a Service

PAAS is Platform as a Service

SAAS is Software as a Service.

It is in layered form with IAAS at its lowest layer then PAAS and topmost is SAAS.

Let me explain you with an example.

Suppose you want to have icecream. Raw materials are milk , sugar, icecream powder. Now you have to decide how to use these raw materials . IAAS is analogous to this.

Next is everything mixed is already given .You just have to freeze it and u ll have the desired product . This is PAAS.

At last , ready made icecream was provided to you and you have the desired product . This is SAAS