JavaScript substring() AND substr()

stringObjectToTakeAPartOf.substring(start-index,stop-index)

• start-index: (Required - Numeric Value) - where to start the extraction
• stop-index: (Optional - Numeric Value) - where to stop the extraction

stringObjectToTakeAPartOf.substr(start-index,length)

• start-index: (Required - Numeric Value) - where to start the extraction
• length: (Optional - Numeric Value) - how many characters to extract