It is a forecasting technique that relies primarily on HISTORICAL time series data to predict the future. What is it?

Moving average or time series what it is but to have a look on history is always a previlage.

there are techniques, but i think  both Trend Analysis & Time-series method  are primarily rely on historical time series data

Time-series method.

Its trend projection

There are many methods for forecasting such Extrapolation of the trend , time series and  Method the slightest squared MMC

http://www.poms.ucl.ac.be/etudes/notes/prod2100/cours/Part%206-Forecast.pdf

Extrapolation of the trend ( used in  the stage of prediction before stage of planning) 

We can say for instance ( Incremental Budgeting ) , Where it's relies primarily on Historical data with some adjustments.

Moving average