This document discusses various types of fishing tools and techniques used in oil and gas well operations. It begins by defining fishing as the removal of debris or equipment from a wellbore. It then describes different types of fishing tools including diagnostic tools, inside grappling tools called spears, outside grappling tools called overshots, and force intensifiers or jars. It provides details on how each type of tool is used to engage and remove objects stuck in the wellbore. The document also discusses milling tools that are used when conventional fishing methods cannot remove an object, and spear fishing tools that use latch fingers to engage with and extract equipment from the well.