Calendars
Calendars are used to give people a way to keep track of the day and to allow people to plan stuff ahead of time. Calendars are normally divided into seven columns and four to five rows. In the four rowed calendar, most of the time the Gregorian calendar, allows for twenty eight days. The other days have to be squeezed in. This is done by taking the last square in the appropriate column of the calendar and then cutting it in half and using that extra half for the extra day. The normal or Gregorian calendar has several pages. The pages are enough to cover that of the twelve months of the year and maybe an extra month (January) because some people are not always prepared.
Calenders
Calenders are one of the most common misspellings of calendars. Most people miss hear or do not emphasize the "are" sound at the end of calendar. Most say calendar with and "er" sound at the end. This convinces the listener to think calendar is spelled calender. The other reason this is a popular spelling is because many words in todays society just have an "er" at the end of it for that sound. Don't worry too much, a lot of people don't' know the difference and there are many ways of correcting and remembering this.
Calandar Form of Calendars
Calandar, another for of calendar is a bit less popular than the one listed above. This is a typical misspelling because it is easy to spell and remember. Now other people may say that that is the hard way to spell calendar, but it is really in the eyes of the beholder. The last form is callender. This is not too far off from the correct spelling, but perhaps it was a simple typo. Callendar could easily be written by a person who is cold and shivering because the calendar says January.