The raster calculator allows you to perform mathematical operations on each cell in a raster. This can be useful for converting and manipulating your rasters. Operators include:
Mathematical (+, -, *, /)
Trigonometric (sin, cos, tan, asin, acos, atan)
Comparison (<, >, =, <=, >=)
Logical (AND, OR)
To perform operations on a raster or rasters, they must be loaded in QGIS.