Open Rate 
Open Rate
The number of HTML email recipients who opened your email, generally measured as a percentage of the total number of emails sent (measurements do vary). The open rate is considered a useful metric for evaluating response to an email campaign but it should be noted that open rates can be deceiving because if a recipient does not download images, an 'open' is usually not recorded.
- A/B Split
- Above-The-Fold
- ASP
- Auto Reply
- Auto Responder
- B2B
- B2C
- Bandwidth
- Blacklist
- Bounce (Hard)
- Bounce (Soft)
- Call To Action
- Campaign
- Can-Spam Act of 2003
- CAPTCHA
- Challenge Response
- Click-Through Rate (CTR)
- Content
- Conversion Rate
- Cost Per Thousand (CPM)
- Database
- Dedupe
- Domain Key / DKIM
- Double Opt-In
- Email Blocking
- Email Client
- Email Newsletter
- Email Service Provider
- eZine
- False Positive
- Font
- From/Sender Address
- From/Sender Name
- Harvesting
- Header
- HTML Email
- IP Address
- ISP
- Landing Page
- Links
- Load Time
- Mailing List
- Multi-Part MIME Email
- Open Rate
- Open Relay
- Opt-In Subscriber
- Opt-Out List
- Opt-Out Subscriber
- Permission Based Email
- Personalization
- Phishing
- Preview Pane
- Privacy Policy
- Rental List
- Segmentation
- Signature
- Single Opt-In
- Spam / UCE
- Spam Trap
- SPF Record
- Spoofing
- Subject Line
- Targeting
- Unique Selling Proposition
- Unsubscribe
- URL
- Viral Marketing
- Web-Friendly Fonts
- Whitelist
