Even though the five-pronged cannabis leaf is an iconic and commonplace shorthand for weed and weed culture, the part of the cannabis plant that people smoke is the flower. It doesn't look like a familiar flower (e.g. a rose, a sunflower), but it functions in much the same way as other bush blossoms. So a lot of cannabis vernacular stems (sorry, pun intended) from the anatomy of the plant. Cannabis can grow really quickly and take over surface area easily, hence "weed" and "bush". You're smoking the part of the plant that blooms, hence "flower" and "bud". But whether it's pot, weed, bud, bush, flower, tree, or jellybeans, it all means cannabis and it all means the same cannabis. In other words, weed is not a different kind of cannabis from flower.
Terms we don't recommend using include "dope," because that gets conflated with several other and sometimes dangerous drugs. We also don't recommend using "marijuana." At a time when most Americans referred to cannabis as hemp, law enforcement started using "marijuana" to stigmatize Mexican immigrants. Marijuana is just the Spanish word for hemp or cannabis.
Terms we don't recommend using include "dope," because that gets conflated with several other and sometimes dangerous drugs. We also don't recommend using "marijuana." At a time when most Americans referred to cannabis as hemp, law enforcement started using "marijuana" to stigmatize Mexican immigrants. Marijuana is just the Spanish word for hemp or cannabis.