Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "Use the command line, your favorite IDE, or your file browser to create a directory somewhere on your machine called MLinJSBook, with a subdirectory called Ch1-Ex1."

A block of code is set as follows:

var items = [1, 2, 3 ];
for (var index in items) {
var item = items[index];
…
 }

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

['landscape.jpeg', 'lily.jpeg', 'waterlilies.jpeg'].forEach(filename => {
  console.log("Decolorizing " + filename + '...');
  decolorize('./files/' + filename)
    .then(() => console.log(filename + " decolorized"));
});

Any command-line input or output is written as follows:

$ node --version
 V9.4.0

Bold: Indicates a new term, an important word, or words that you see onscreen. 

Warnings or important notes appear like this.

Tips and tricks appear like this.