Every template is filled at send time from your account data, so nothing needs to be typed in:

• Company details from Client Config: business name, email, phone, logo, description, address, zip, state, country code, latitude/longitude, primary/secondary colours and text-on-colour colours, Facebook/Instagram/Twitter/Yelp/TikTok/WhatsApp links and your website address. Some texts (for example the checkout email's footer note) also use «client_name», «client_email», «client_phone» and «base_url» tokens that get swapped for those values.
• Customer details: first and last name, email and, where relevant, birth date or first/last order dates.
• Event details: order number, items, totals, delivery/pickup date and address, gift-card code, referral code, subscription plan, password-reset link, email validation code, and so on, depending on the email.

The subject line is written into each template individually: some are fixed text (for example Registration for New Registered User, Recover Password for User: Recovery), while others build in a live detail - the Order: Create email's subject is Checkout #<order number>. The same company details are what the newsletter popup title uses when it shows «client_name».