There is a very good article on cateracts at www.mayoclinic.com. Their write-ups on diseases and procedures are excellent and trustworthy. The article describes the different types of cateracts, describes the operations, care, problems, etc.
MMario, cateracts developing with old age require an implant. That is what I must have done. The article discusses the different types.
Mayo Clinic write-up: Cataracts
You may wish to go to the first page at www.mayoclinic.com and look up other conditions.