The website Craftsy writes that five of the most common knitting cast-on methods include the long-tail cast on, the knit cast-on, the cable cast-on, the loop cast-on and the crochet cast-on. Knitting at Large created a more extensive catalog of cast-on techniques, including the rare Turkish and Mobius versions.
Both Craftsy and the catalog from Knitting at Large provide video links showing how to do each different cast-on technique. Lion Brand Yarn has a tutorial on casting on using the easy and popular knit method, which they describe as good for beginners. They further advise that CO is the abbreviation used in knitting patterns to note the method of cast on and the number of stitches.
A search on Pinterest leads to a large variety of different cast-on techniques. Many of the techniques include short notes about what they are best used for, so when conducting a search the knitter can also use search terms related to the type of project or edge desired in order to find the best cast-on method. Those who are struggling can typically find videos that knitters have created illustrating the various methods, with one example being a video of the circular cast-on, a method used for in-the-round knitting projects which start with just a few stitches.