For something that's been around for only about the last couple of decades, email has become an essential part of our lives. Whether it's sending a message to a coworker, greeting a friend, or sending a shopping list to a significant other, we use email all the time in every possible way. According to one study, workers spend on average 78% of their typical, 8-hour workday checking their email.

Intranet software maker Igloo recently surveyed 2,000 workers who use email to discover their email habits, preferences, and pet peeves. Here are 8 of the most egregious email pet peeves revealed by Igloo's study-which ones are you guilty of?

1. Spam (81% of workers say that the spam they receive is annoying)

2. Irrelevant emails (66% of workers say that the irrelevant email messages they receive are annoying)

3. Obnoxious or insincere signature (50% of workers say that they are annoyed by obnoxious or insincere email signatures)

4. Lag in response time (48% of workers reported that a lag in response time to their messages bugs them)

5. Back-to-back emails from the same person before you've had a chance to respond (42% of workers say that this annoys them)

6. Emoticons (27% of workers are annoyed when they receive email messages with emoticons)

7. Group emails (25% of workers are not particularly happy when they are included in group email messages)

8. Exclamation points (22% of workers report that the use of exclamation points annoys them!!!)