There are two modes of experience, which we could call attention and awareness.
Attention is a little like the fovea (the centre of the visual field): it can only include one thing at a time, but it’s highly detailed, whereas awareness is a little like peripheral vision: it creates a general impression and includes a huge amount of information all at once.
Attention is very familiar to most people; everybody knows what it feels like. We usually pay attention in order to understand or use the things we’re attending to. When we use attention to know things, they appear static, decontextualised, fixed, defined. Attention is more narrow, focused, conceptual, and goal-oriented. You’re paying attention to these words right now!
Awareness, on the other hand, is open, spacious, holistic, and non-conceptual.
We are aware of the forest we’re walking in, and that it’s beautiful, without needing to pay attention to precisely what individual features make us feel precisely which moment to moment feelings. Indeed if we were to scan with attention to try to pin down where the beauty is coming from, we’d probably lose a sense of that ineffable spiritual joy and just get stuck in thoughts or analysis.
It can seem less certain whether we’re actually knowing with awareness or not because we think that knowing only counts if we do it with attention. When hearing about this distinction, attention seems so sure and clear, and awareness feels indistinct and uncertain. People often try to pay attention to awareness to make it clearer, which is like trying to look directly at your peripheral vision to see more clearly what it’s like; it misses the point that these are two different kinds of knowing.
But let go of any effort for a moment; let go of trying to conceptually understand, pay attention to, use, make sense of, or make clearer the contents of awareness. Right now, as your attention is on these words, you are still effortlessly aware of other things. In fact your awareness is replete, with the sounds around you, where you are, your degree of comfort, degree of contentment, your active goals, your energetic and emotional state, if anything around you requires a response, and all kinds of other stuff. Awareness provides a holistic sense of how we are, and the context within which attention can be recruited to what’s relevant.
Attention and awareness are both always present, but one can dominate - and for most of us it’s usually attention that dominates! For example, if we’re walking in a forest, there’s a lot of potential beauty in that experience, but if we’re strongly attention-dominated; lost in thought, or paying close attention to something in particular, we lose the openness to that sense of beauty.