Difference between 各 and 每? I'm used to using 每 for every. However, 各 came up one day and appears to me to have the exactly same meaning. Is there a contextual difference between the two that I am missing or can they be swapped for each other? When should someone use 各 instead of 每?
各 is more like "each". It is more frequently used when the intention is to describe some sort of individuality of some group. It is more common to see this character in describing the difference in each item in a group. Example: 各种不同的花 (many different kinds of flower).

每 is more like "every". It is used more when the intention is to describe a group's collective property that all members share, and consequently seen more often when describing the sameness of items in a group. Example: 每种花都一样 (all the flowers are of the same kind).

The confusion is that they are both used when describing some property of the individual in a group, but with different intentions. You can see them as two kinds of "every" with different connotations.