user138433: As far as (voting) on the network?
I run a full node, but do not mine.
I hear people say we have a choice when changes are made.
Is it the version of Core that determines that?

user5406: There is no vote on what the rules of the network are, and your own node has no influence on the rules other nodes enforce.
Fully validating nodes (aka full nodes) locally enforce all rules of the Bitcoin protocol. A node operator expresses what they consider to be Bitcoin by deciding which node software to run. Since a node will reject any blocks or transactions that break its rules, the node operator can be sure that whatever blockchain their node shows follows the rules that they wish to enforce.
If a majority of the hashrate enforces stricter rules than some node, the stricter ruleset will produce blocks that are acceptable to those with looser rules. This can be used to introduce rule changes in a so-called soft fork: soft forks tighten rules and thus are forward-compatible to less-strict Bitcoin software. This makes the general rules on the network emergent. The network rules emerge from many users making a choice about the software they are running and the common denominator being enforced by the economic majority.
However, if a minority of the nodes enforces stricter rules than the majority of the network (without support of a majority of the hashrate), they will reject the longest chain and end up stuck on a stale chaintip.
To give some concrete examples:

a miner may choose to miner smaller blocks than allowed
a miner may choose to exclude inscriptions from their blocks
a node that unilaterally decides not to accept blocks with inscriptions will stop following the best chain
a miner that mines a bigger block than the majority of the network permits will see its block rejected


138433: <p>As far as (voting) on the network?
I run a full node, but do not mine.
I hear people say we have a choice when changes are made.</p>
<p>Is it the version of Core that determines that?</p>
 5406: <p>There is no vote on what the rules of the network are, and your own node has no influence on the rules other nodes enforce.</p>
<p>Fully validating nodes (aka full nodes) locally enforce all rules of the Bitcoin protocol. A node operator expresses what they consider to be Bitcoin by deciding which node software to run. Since a node will reject any blocks or transactions that break its rules, the node operator can be sure that whatever blockchain their node shows follows the rules that they wish to enforce.</p>
<p>If a majority of the hashrate enforces stricter rules than some node, the stricter ruleset will produce blocks that are acceptable to those with looser rules. This can be used to introduce rule changes in a so-called <em>soft fork</em>: soft forks tighten rules and thus are forward-compatible to less-strict Bitcoin software. This makes the general rules on the network emergent. The network rules emerge from many users making a choice about the software they are running and the common denominator being enforced by the economic majority.</p>
<p>However, if a minority of the nodes enforces stricter rules than the majority of the network (without support of a majority of the hashrate), they will reject the longest chain and end up stuck on a stale chaintip.</p>
<p>To give some concrete examples:</p>
<ul>
<li>a miner may choose to miner smaller blocks than allowed</li>
<li>a miner may choose to exclude inscriptions from their blocks</li>
<li>a node that unilaterally decides not to accept blocks with inscriptions will stop following the best chain</li>
<li>a miner that mines a bigger block than the majority of the network permits will see its block rejected</li>
</ul>
