Weeding has been the bane of humanity since the dawn of agriculture. For about 70 years, synthetic herbicides have removed much of the drudgery of this onerous task. Glyphosate was introduced as a non-selective herbicide in 1974. Its ideal properties made it a very popular herbicide, and the introduction of glyphosate-resistant (GR) crops allowed its use as a selective herbicide, greatly expanding its use to become the most used herbicide on earth. For farmers who used glyphosate in GR crops, it was the golden age of weed management, as this technology significantly improved the efficacy and reduced the cost of weed management. Weed management was also simplified, an asset that was particularly valuable to part-time farmers. Furthermore, this technology provided the environmental benefits (reduced soil loss and fossil fuel use) of significantly reducing tillage. Farmers saved billions of US$, and weed management became more effective and simple. Indeed, to many farmers, glyphosate with GR crops became the goose that laid the golden egg. After more than 20 years of use, the first cases of GR weeds were reported in the latter 1990s. After a lag period of less than 10 years after the first GR weed was reported, the number of species reported to have evolved glyphosate resistance began to increase in a linear fashion, reaching 53 species in 2021, third only to atrazine (66 species), a much older herbicide and to ALS inhibitors (168 species), which include several different herbicides used in numerous crops since the 1980s. The long lag phase before any resistance was detected led some to believe by the mid-1990s that evolution of resistance was improbable. By this time, glyphosate use was greatly increasing, especially in GR crops, an ideal situation for the evolution of resistance. After this, the number of glyphosate-resistance cases exploded, and the mechanisms of resistance to many of these cases of resistance were determined. A recent, short commentary detailed these mechanisms after a new mechanism of resistance was reported. The number of mechanisms for resistance to no other herbicide comes close to those of glyphosate. In the present paper, we briefly describe the many evolved mechanisms by which weeds have evolved resistance to glyphosate.