Conventions used

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

Code in text: 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: "For example, the following sample JSON specifies configurations for the core-site and mapred-site classifications and includes Hadoop and MapReduce properties with values that you plan to override in the cluster."

A block of code is set as follows:

    "Properties": {
      "mapred.tasktracker.map.tasks.maximum": "10",
      "mapreduce.map.sort.spill.percent": "0.80",
      "mapreduce.tasktracker.reduce.tasks.maximum": "20"
    }

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

    "Classification": "core-site",
    "Properties": {
      "hadoop.security.groups.cache.secs": "500"

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

aws emr create-cluster --instance-type m5.2xlarge --release-label emr-6.4.0 --security-configuration <mySecurityConfigName>

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: "If you are creating a transient cluster that needs to execute a few steps and then auto terminate, then you can select Step execution for Launch mode."

Tips or Important Notes

Appear like this.