Your pictures are of no help to identify a pest. Since you've mentioned that these yellow 'bugs' are on so many different kinds of plants. I'll suggest that you might have aphids. A quick 'google' will allow you to compare zillions of on line images with what you have. Aphids are probably one of the most common of plant pests, by the way. Let us know what you decide: aphids or not.

Carpebio, you know, I really don't think that aphids are your primary problem, after all. I DO see a couple of little winged insects, and wonder if they might be leaf hoppers. If there are aphids, you'd have hoards of them. The damage we can observe would be more indicative of the leaf hoppers, though spider mites is a clear possibility with all that speckling on the foliage.

Have you done (or know how to do) an inspection for spider mites?

I've attached a Google images page for the (ubiquitous) Potato Leaf Hopper. These little guys can be found on all kinds of plants, including herbs. The damage is very similar to yours.

So! You've got some homework. Compare what you've observed with aphids, leaf hoppers, and check for spider mites.

Here is a link that might be useful: Click here

Agreed, they are not aphids. Probably leaf hoppers.