LaaS (Infrastructure - as -service) The users can get service from computer infrastructure though internet.The user does not control the infrastructure.
PaaS(Platform -as - a - service):The service given to the user is to install on infrastucture of cloud system by user itself or acquired application that may be written in programming language and using tools provided by the service provider. The end user can control the installed applications but he can not control the infrastructure of cloud computing system .Actually,PaaS is another application of SaaS.It makes SaaS develop faster.
SaaS(Software - as- a - service):It is a kind of pattern via internet provide software.The customer use application which are easily accessible from client device and does not control the cloud infrastructure including network .operating system and so on.
