Big data, in the context of CRM, relates to large volumes of data used for (mostly predictive) analytics.
Data can be collected from various sources including customer channels, transactions and other customer activities such as product usage.
By applying analytics to these large volumes of data customer patterns, associations and trends can be identified. This can then be used to predict behaviours and outcomes.
Benefits can include better decision making, predictive modeling, and benchmarking.
This means that, for example, Marketing, Sales or Service reps can be equipped with insights to identify hot leads, close sales faster, predict when service issues can blow up.