时域是数学函数的物理信号或时间序列的经济或环境的数据，相对于时间的分析。在时域中，信号或函数的值是已知的所有实数，对于连续时间的情况下，或在离散时间的情况下的各种单独的时刻。示波器通常是用于可视化真实世界的信号在时域中的一个工具。时域图显示的信号如何随时间变化，而频域曲线图显示多少信号的频率范围上的每个给定频带内的所在。-Time domain is the analysis of mathematical functions, physical signals or time series of economic or environmental data, with respect to time. In the time domain, the signal or function s value is known for all real numbers, for the case of continuous time, or at various separate instants in the case of discrete time. An oscilloscope is a tool commonly used to visualize real-world signals in the time domain. A time-domain graph shows how a signal changes with time, whereas a frequency-domain graph shows how much of the signal lies within each given frequency band over a range of frequencies.