All the wrenches are made for the same task that is tightening or loosening something like nuts or pipes. Different types of wrenches are there are for different purposes. For example, an open-end wrench fits around a fastener, so it is more useful to work in hard to reach places.
We will go through the most used and common wrench types. There are wrenches for standard (SAE) fasteners and also for metric applications. Usually, there is standard or metric code is written on a wrench.
This kind of wrench does have a moveable jaw to adjust wrench size. It works great with both standard and metric fasteners. It is mostly used to tighten/loosen nuts and bolts.
The main purpose of combination wrench also is to tighten/loosen nuts and bolts. It comes with both Metric and standard sizes and it is usually written on the wrench. Usually, the open end and the box end are of the same size. The open-end wrench is used to reach difficult areas, where as box-end used for loosening stuck fasteners.
Open-End wrenches also have two types: Single headed and Double headed. Usually, a double headed open-end wrench has two open ends of different sizes. These wrenches also come for both Metric and standard sizes. There are also joined or flex-head models which give you more comfortability to work at different angles.
See our guide to buy the best open-end wrench set.
These types of wrench usually have an open-end wrench in one end and ratchet on the other end. Ratchet action on one end moves freely in one direction and locks the fastener in the other direction to tighten or loosen without removing the tool. Some of them do have pivoting ratchet ends for use in tight spaces.
These wrenches do not have any handle. It is only the head which comes in both metric and standard sizes. To work with them a ratchet handle/socket extension is needed. Great to work in tight spaces and can generate high torque.
Hex Key Wrench
These wrenches are made to tighten/loosen hex-head screws and bolts. These also come with both standard and metric sizes. Usually, sold in a set of different sizes. For improved leverage, few come with T-handles as well.