ult. from Lat. referre, 'to carry, bring, or drive back'
(usu. w/'to') to report, to give an account of
(legal, usu. w/'back') to have retroactive effect
(usu. w/'to') to reference, to refer to
(usu. w/'to') to have a connection with, to stand in relation to
(usu. w/'to' or 'with') to bring into relation with, to establish a relationship between
to connect, to link
(w/'back to') to derive from, to stand in relation to sth past
(w/'to') to feel empathy for, to feel a connection with
some obsolete senses
the past part. of Eng. relate, 'to have been or come into relation'
(also in compounds) [mutually] connected to, having [mutual] relation to
connected by blood, belonging to the same family
(biol.) sharing an ancestor
some obsolete senses, incl. noun use via Lat. relatum ('related [thing]')
ult. from Lat. relevans, 'lightening, easing, relieving'
In other words, the first two are synonyms w/r/t connected concepts.
These recommendations relate to the details of our data storage proposal.
These recommendations are related to the details of our data storage proposal.
'These recommendations are relevant to the details of our data storage', on the other hand, implies they have an importance to your data storage but may not themselves directly discuss it. They just have some kind of significant effect upon it.
They're not synonyms w/r/t people.
I relate to her or I can relate to her. [I empathize with her experience, thoughts, and/or feelings.]
I am related to her. [She belongs to my family.]
I am relevant to her. [She values my opinion, although it's an odd sentence.]
They're not exact synonyms w/r/t narratives or accounts.
I related the report to him. [I told him about the report.]
I am related the report to him. [This is nonsense.]
The report was related to him. [Someone told him about the report.]
I am relevant the report to him. [This is nonsense.]
The report was relevant to him. [The report had some significance to him.]
They're not exact synonyms w/r/t to references to the past.
The report relates back to the incident in July. [There is a mention in the report about the July incident.]
The report is related to the incident in July. [*The report caused or is mainly concerned with the July incident.*]
The report is relevant to the incident in July. [The July incident should be understood at least in part based on an understanding of the report.]