General endorsements

Below is a small selection of products which I have found to be of high standard, and can therefore recommend. 

Software

IrfanView.  Software for viewing and editing images. 

MATLAB.  Software for mathematical computations.  Not entirely free of bugs, and suffering unnecessarily difficult/limited graphical export of images, but generally robust, reliable and powerful. 

Books

Bilingual dictionaries published by Collins in European languages:  German–English, Italian–English, French–English.  Both large and small (Pocket or Gem) versions are good.  In contrast, their Korean–English Pocket dictionary is not recommended.