Abbreviations are one of the methods I teach for writing faster. I stress writing neatly and that the symbols be of consistent form. This has extra importance because we do not dot the letters " i, j " or cross the letter " t ".

Printing is slow, so we do not print "PPM". We write the abbreviation for " parts per million. The letter " p " is particularly important because if it is formed sloppily, it may look like an undotted j. Finally note the abrupt ending of the final letters.