Clean code is the term given to the philosophy of writing code that is understandable and easy to modify. Clean code became conceptualized with the book 'Clean Code: A Handbook of Agile Software Craftsmanship,' published by software engineer Robert Cecil Martin in 2008. The book discusses principles to follow and avoid when writing clean code, with examples.

What is Clean Code?

Clean code is a technique for writing code that is easily understood, readable, and maintainable by another programmer. In addition to being functional, it ensures the healthy continuation of the software lifecycle. Clean code is an accepted and important concept in the software world.

If code is not clean, it is referred to as 'bad code.' Bad code is characterized by becoming increasingly complex from version to version and being incomprehensible when reviewed by a team other than the one that wrote it. Clean code emerged due to the increase in costs associated with code editing and even the closure of software companies.

What are the Principles of Clean Code?

Clean code is a style of coding that has principles. These principles, which encompass the values of clean code, are applied in many stages such as naming, object and data structure, function writing, and comments. The principles of clean code are as follows:

1. Code should be readable and understandable.
2. Avoid unnecessary repetitions.
3. It should be simple and consistent.
4. The code should contain only the necessary code that the project really needs.

How to Write Clean Code?

Clean code is written by adhering to the aforementioned principles. To facilitate team communication, it is recommended to create a suitable clean code handbook for the project before starting. Let's take a look at the details of how to write code in accordance with the practice of clean code.

The programmer assigns names to functions, classes, and objects within the code according to their own understanding. According to clean code, the names to be used in the code should be as follows:

• Clear and unambiguous in meaning
• Not referring to another meaning
• Not evoking the same meaning
• Pronounceable
• Findable in a search
• At least two letters long

The characteristics of clean code for functions, which are the building blocks of programming, are as follows:

• Should be as small as possible.
• Each function should have a purpose.
• All expressions within the function should be at the same level of abstraction.
• The 'switch' statement should be kept to a minimum whenever possible.
• Should not contain side effects.
• Within the code, programmers add reminder, warning, and informative notes as comments between lines. Comments are necessary and useful. 

According to the philosophy of clean code, good comments are as follows:

• Legal notifications related to the code
• Informative notes specific to the code, such as date format
• Notes describing the purpose of code lines
• Code outputs
• Warnings
• Requirements for the code to function

What are the Benefits of Clean Code?

There are many benefits and advantages to writing code while adhering to clean code principles. These include:

• The language used is understandable by everyone.
• Reduced complexity during version transitions.
• Formation of a universal code standard.
• Suitable for corporate use.
• Easy to test.
• Extended lifespan of the project in which the code runs.