What is the SMTP host name for Google?

Could you please clarify for me what the SMTP host name is specifically for Google? I'm trying to set up an email client and I'm having trouble finding the correct information. Is there a specific format or naming convention that I should be aware of when it comes to Google's SMTP host name? Additionally, are there any security measures or authentication steps that I need to take into account when using this host name? Thank you for your assistance.