This chapter is very important from the point of view of product portfolio analysis the entire chapter is made up of you can say product portfolio analysis abhi kya hota hai ye product portfolio analysis now it is the bunch of products offered by the company to the people it can be for example Maruti Suzuki cars right they offer very low segment cars, medium and high segment cars right for all different, different pockets ya phir you can call it as different, different segment correct and which needs to be updated on regular basis and they need to see that whether their sales are not decreasing for that for that reason they need to update such things again and again they need to be constant in touch with the market conditions that is product portfolio analysis check in, analyzing again and again what product are you offering to the costumers, costumers are happy, they want some kind of change, what they want, strategic business unit, analyzing portfolio may be begin with identifying key business, also termed as SBU now SBU can be a company division, a product line, even a single product or it may be a brand right is SBU, has a own set of competitors, has manager responsible for strategic planning and profit single business or collection that can be planned for separately, experience curve similar to learning curve which explains efficiency gained by workers through repetitive productive work. Lager firms have lower unit cost compared to smaller firms. Now let us see alright all these three important concepts to understand different models of portfolio analysis. Now very first we see PLC product life cycle, here the main advantage of PLC is that it can be diagnose portfolio of products in order to establish the stage at which each of them exist, now here in we are gone see right the life cycle, the product life cycle right kids on the X axis we have time right.