Measurement of essential process parameters that impact critical quality characteristics is at the heart of process analytical technology (PAT), which is used in the design, analysis, and control of pharmaceutical production processes. Physical and Chemical Attribute Testing (PAT) ensures high quality raw materials (i.e. at off-line, on-line, in-line). With PAT, we move away from testing the structures themselves and instead test the goods themselves at various stages of production. PAT drastically reduces the resources needed for product sampling and testing. In order to be effective, PAT must provide instruments such contemporary process analysers or analytical chemistry, endpoint process monitoring and regulating instruments, and continuous improvement and knowledge enhancement instruments. In this review, we've tried to dig into what PAT is, what it's for, what kinds of tools you can use for it, what problems it's meant to solve, how it operates, and what advantages it offers.