How to merge 4 adjacent, coplanar faces into a single face I have a plane consisting of 4 squares - take as an example a subdivided plane. How can I merge these faces into one?
There is an operator called Dissolve which does exactly what you want. 

Select everything, with A, and then press X (or Delete) and select Limited dissolve. This will do the same thing as above, but will not require you to select the proper vertices manually.