TL;DR

If you are in software testing business, and you want to be recognized as skillful tester, you need to know software testing definition by hart. This is Black Box Software Testing Definition of software testing.

Definition Of Software Testing

Software testing is

• empirical

• technical

• investigation

• conducted to provide stakeholders

• with information

• about the quality

• of product or service under test

Which sums to that you as a software tester design and run tests in order to gain useful information about the products quality.

Empirical Investigation

based on, concerned with, or verifiable by observation or experience rather than theory or pure logic: they provided considerable empirical evidence to support their argument.

Which means that as a tester you need to provide investigation evidences that are observable or could be explained by experience. For example, you have a test where search in Amazon store for snickers returns error instead of not found. Your experience is that snickers is highly probable search item in Amazon store, and you provide observable evidence that test failed.

Technical Investigation

 is investigation that requires special knowledge to be understood. For example, product domain knowledge, technology knowledge (e.g. HTTP protocol).

Stakeholders And Values

Before you start testing, you need to know who are your stakeholders:

A person with an interest or concern in something, especially a business.

And what is their product value. After that, you will design tests with goal to find information what is current product quality in context of each stakeholder.

Your grandma iPhone interest is battery duration, and your sister interest is execution smoothness of Fortnite game. Your first test is to play Fortnite, and your second test is to just use voice call and iMessage features in iPhone low power mode.