Desk note
Slots, blocks, and why two explorers disagree for a minute
Visitors sometimes arrive with two browser tabs and a worry that one of them is false. Both tabs are showing the same signature. One says the transaction is confirmed. The other still speaks more softly, or has not attached a block time yet. That minute is ordinary, and it is worth knowing what you are looking at before you refresh in a panic.
Slot, parent, block
A slot is a turn in the schedule. Some slots produce a block and some are skipped. A block page carries a blockhash, a parent slot, and a list of transactions. When you cite a page, write the slot and the signature. The block height, when the explorer shows it, is a different counter from the slot number. Treating them as one number is how notes drift.
The parent slot tells you which earlier block this one claims to follow. You do not need to walk the whole chain in a sitting. You do need to notice when an explorer is showing you a block header rather than a single transaction. They are neighbouring pages, and the fields change.
Commitment, said plainly
Processed, confirmed, and finalized are degrees of how widely the cluster has agreed. Explorers do not always use the same word at the same moment. A page can be useful for reading the fee payer and the instructions before it is finalized. If you are saving a note for someone else, wait until the explorer you trust shows the stronger commitment, then record the slot, the time, and the signature together.
The desk does not run an explorer. We read the ones you already have open. If two of them disagree, we write down what each one showed and the minute on the clock, and we look again when the room's tea has gone cold. That is usually long enough.