A signal is a time-varying quantity of data; it can have a name, data type, numeric type, and one- or two-dimensionality (vector or matrix).
By wiring blocks together, Embed can pass signals among blocks during a simulation. Input signals (xn) represent data entering blocks; output signals (yn) represent data exiting blocks. Most blocks can receive or send any type and dimensionality of a signal; however, some blocks do have restrictions on the type of data they can act upon. The individual block description lists the restrictions that apply to the block.