1 with different generation times:
Help-after the criminal suspect is interrogated by the investigation organ for the first time, or from the date when compulsory measures are taken. In other words, legal aid is limited to the investigation stage.
Defense-the time when the defender of a public prosecution case is produced is the date of transfer for examination and prosecution, and a criminal defender can be entrusted at any time for a private prosecution case.
2. Different identity requirements:
Help-In criminal cases, only lawyers can provide legal help.
Defense-the defendant's defender can be a lawyer or a relative.
3. Enjoy different rights
Help-lawyers who provide legal help have five rights: to provide legal advice, to represent complaints and accusations, to apply for bail pending trial, to meet suspects and to know the charges.
Defense-the rights of criminal defenders vary according to whether they are lawyers or not. Specifically, there are the following kinds: the right to independent defense, the right to read papers, the right to meet, the right to investigate and collect evidence, and so on. Lawyers and non-lawyers are different in defense. I won't elaborate.
That's all I can say. As for the difference in meaning, I am too ignorant to give an answer.