 So, now in this video we will study about the types of microscope as in your syllabus there is only one type of microscope that is simple microscope, but let me tell you few more description about the how many types of microscope are there and where are they used. So, write out in the notebook if you have types of microscope, the three types of microscopes first is simple as this microscope was used for the discovery of the cell which contains two lens that is bi-convex lens, second is compound microscope as it is clear by the name it is compounded means it is little complex as compared to simple microscope, compound microscope is basically used to see the specimens and slides that is used in the schools and colleges. The microscope that you see in your lab if you are in a school or college that is normally compound microscope, third is electron microscope that is the latest microscope and that is only used in the laboratory where the researches are going on. So, you can easily classify that research, laboratories, microscope is electron microscope. So, what is the basis of classification of these three type of microscope though the normal basis is the magnification. Magnification is directly related to the clarity of the image that is the image clear or is it fine or not fine. So, simple microscope does not give the fine image of the specimen or the slides then compound microscope is better than the simple microscope as its magnification power is greater as compared to simple and the most latest is the electron microscope that is functioning on the basis of the electron beam that is the most magnified or their magnification is higher if we compare. So, these are the three types of microscope, illuserables is simple microscope, but you should also know that what is compound and electron microscope a little bit. After this as we are seeing that microscope leads to so many discovery, discovery of different type of cells, what is their structure, what is their function, how they are differentiated from various cells like animal cell, plant cells, microorganisms cells and pathogen cells. So, now we will study about the cell theory. Cell theory was given by the scientists Sladen and Schwann in the year 1838 and 1839. So, important is cell theory as the cell was discovered the two more scientists whose name is Sladen and Schwann always remember the two scientists for the cell theory is Sladen and Schwann they both work together and then they both proposed a theory in which there was some points. So, mainly you have to learn about the two basic points that was in cell theory first we should write down the name of the scientist Sladen and Schwann first remember the year 1838 and 1830. Next what are the two points of this theory? The first point is the basic point that you are studying in the starting of the chapter that cell is the structural and functional unit of life. Cell is the structural functional unit of life and the second point is before learning the second point learn this statement Omniscellular Ccellular. So, this statement is that all the cells arises from the pre-existing cells for example, if there is this is one cell it will undergo division it will form two cells. Now, this will also undergo division two cells similarly with this. So, how many cells? 1, 2, 3, 4. So, these cells are originated from the pre-existing. So, for these cells these are the pre-existing and for these cells this is the pre-existing cell. So, the second theory state that all the cells arises from the existing cells. So, these are the two points of cell theory that was given by Skledon and Sean in the year 1838 and 1839. Cell is the structural and functional unit of life and Omniscellular means all the cells arises from the pre-existing cells. After this we will know that what are the types of cell and what is the basis of Omniscellular Ccellular Ccellular classification in next video.