greek letters
In engineering, electrical engineering, electronics and communications engineering, various units and dimensions are designated with Greek letters.
For example, the unit used for resistance is the Greek letter 'omega' in upper case, and in lower case 'omega' it is the angular frequency. And the specific resistance is given in small rho `rho`. For the wavelength the small `lambda` is used and for the magnetic conductance the large `lambda`. The large `phi` for the magnetic flux and for angular values the small `alpha, beta` or ` gamma` and so on.