Example:
One day, a cell phone company wanted to do a UI automation test, so they hired an engineer.
The first thing this engineer needs to do is SETUP an automated test environment. In that respect alone, a test engineer and an automation engineer need to do exactly the same thing. For example, setup a complete UiAutomator environment.
After that there is a difference. Once the environment is set up, the test engineer's main focus will be laid on writing scripts and executing tests. Automation engineers, on the other hand, will focus on how to optimize the UiAutomator environment
For example, we all know that after a UiAutomator case is written, it first needs to be compiled by ant, and then pushed by adb commands before it can be executed. At this point, generally the test engineers wouldn't have done anything to change it, but the automation engineers would have made a program or batch or whatever to make these steps a point-and-click-and-do-it-all kind of thing.
What is test automation:
It is a change that takes the testing process away from manual labor. It is a development process that has a positive impact on cost control, quality control, quality recall, and test cycle reduction.
What is automated testing:
A type of testing that is done by handing over part of the test execution partially or completely to a machine is called automated testing. This type of testing does not require real-time human involvement. At the same time this type of testing can be much more expensive than manual testing in small scale applications.
Automation testing can be seen as a part of test automation.
Different engineers, different jobs:
An automation engineer will be more focused on the development of test tools. The main thing is that this engineer will think in terms of cost. This is more like a PM, who does everything to reduce his or his team's workload by coding and automating repetitive, regular tasks as much as possible.
An automation test engineer focuses on developing test code and analyzing test results. They are very interested in the device under test itself. They tend to be a bit of a perfectionist, striving for high quality and often ignoring cost. This is more like a developer.