Tonight, I did a round of screening and classification of several hot sectors in the US stock market.

I also briefly noted the core logic of each category, the main business of each stock, and market focus points.
This is basically the start of my formal dive into US stock research.
My current view on US stocks is:
The mainline sectors are still the directional indicators, but many core stocks have already risen to high levels. Chasing them hard now has a generally poor risk-reward ratio.
They are stable and represent the trend, but they may not be the most comfortable entry points at the moment.
At this stage, the more noteworthy opportunities lie in the diffusion of the mainline and the spillover of the industrial chain.
For example, in major directions like AI, robotics, computing power, data centers, semiconductors, and crypto finance, after the core leaders have rallied, capital often continues to seek second-tier elastic stocks in the chain, laggards with upside potential, and companies whose logic has not yet been fully priced in.
These types of stocks are the ones that may still have room and potential.