An example of the distinction is Bettini v Gye (1876) 1 QBD 183, where Bettini agreed to perform in London between March 30 to July 13 1875 and was supposed to be in London 6 days before rehearsals. He arrived on March 28 ready to perform but Gye refused to accept the performance. The court held that arriving 6 days before was not a "condition" (term) of the contract, so breach did not "go to the root of the contract". The contract did not state anything like "if you are not here 6 days before the contract is cancelled". The court made this distinction:
Parties may think some matter, apparently of very little importance,
essential; and if they sufficiently express an intention to make the
literal fulfilment of such a thing a condition precedent, it will be
one; or they may think that the performance of some matter, apparently
of essential importance and primâ facie a condition precedent, is not
really vital, and may be compensated for in damages, and if they
sufficiently expressed such an intention, it will not be a condition
precedent.
Breach of a condition allows the offended party to repudiate the contract, but breach of a warranty does not enable a contract to be repudiated. The Sale of Goods Act 1979 section 11 encodes the distinction thus:
Whether a stipulation in a contract of sale is a condition, the breach
of which may give rise to a right to treat the contract as repudiated,
or a warranty, the breach of which may give rise to a claim for
damages but not to a right to reject the goods and treat the contract
as repudiated, depends in each case on the construction of the
contract; and a stipulation may be a condition, though called a
warranty in the contract
In other words, you can tell if something is a term vs. a warranty if there is a breach and you try to repudiate the contract, and the court says "No you can't do that", and that's how you know that it was a warranty and not a term. (There are probably better ways, but it's like Fair Use in its subjectivity).