  The continuous advances in data collection and storage techniques allow us to
observe and record real-life processes in great detail. Examples include
financial transaction data, fMRI images, satellite photos, earths pollution
distribution in time etc. Due to the high dimensionality of such data,
classical statistical tools become inadequate and inefficient. The need for new
methods emerges and one of the most prominent techniques in this context is
functional data analysis (FDA).
  The main objective of this article is to present techniques of the analysis
of temporal dependence in FDA. Such dependence occurs, for example, if the data
consist of a continuous time process which has been cut into segments, days for
instance. We are then in the context of so-called functional time series.
