Clean Code


Points to remember
Make it easy to read,
Make the surrounding code clean,
Change one variable name for the better,
Break up one function that’s a little too large,
Eliminate one small bit of duplication,
Clean up one composite if statement.
Use meaningful names
Distinguish names in such a way that the reader knows what the differences offer
Use Pronounceable Names

Functions
Functions should be small. They should do one thing. They should do it well. They should do it only.
We want to read the code like a top-down narrative.
Use descriptive names for functions.
Switch statements should be buried deep in a low-level class and should never be repeated.
Use Descriptive names for the functions. The smaller and more focused a function is, the easier it is to choose a descriptive name.
For a function three or more arguments should be avoided. Ideal is zero arguments.
Flag arguments are ugly.
When a function needs more than two or three arguments then wrap the arguments into a class of their own.
Functions should either do something or answer something, but not both.
Extract the bodies of the try and catch blocks out into functions of their own.
Duplication may be the root of all evil in software. Many principles and practices have been created for the purpose of controlling or eliminating it.

Comments
Adding comments is not good as it shows your failure in writing an expressive code.
Either spend your time writing the comments that explain the mess you’ve made or spend it cleaning that mess.
Don’t Use a Comment When You Can Use a Function or a Variable
Comments are good only if they
Meant for legal documentation
Provide Informative value for a complex regular expression or formula
Explain the intent or business requirement
Clarify the third party library or API usage
Warn about consequences
Denote TODO tasks
Amplify the importance of something

Formatting
Code formatting is about communication, and communication is the professional developer’s first order of business
A team of developers should agree upon a single formatting style, and then every member of that team should use that style.
The reader needs to be able to trust that the formatting gestures he or she has seen in one source file will mean the same thing in others.
Vertical Size: Small files are usually easier to understand than large files are
Source file should appear like a newspaper article.
Horizontal Size:  Strive to keep our lines short