Metrics:

Numbers used as a measurement for standard of quality for comparing different items or time periods. Visits, Unique Hosts, Goals, and Value are all fields that might be used as a metric.
Often used interchangeably with measurements. However, it is helpful to separate these definitions. Metrics are the various parameters or ways of looking at a process that is to be measured. Metrics define what is to be measured. Some metrics are specialized, so they can't be directly benchmarked or interpreted outside a mission-specific business unit. Other measures will be generic, and they can be aggregated across business units, e.g. cycle time, customer satisfaction, and financial results. 
A prescribed set of measurements to track product development and allow a firm to measure the impact of process improvements over time. These measures generally vary by firm, but may include measures characterizing both aspects of the process, such as time to market, and duration of particular process stages, as well as outcomes from product development such as the number of products commercialized per year and percentage of sales due to new products.