Easter, the Christian holiday celebrating the resurrection of Jesus Christ, is one of the oldest Christian holidays and is often considered a convergence of Christian, Hebrew, and Pagan cultures. The New Testament of the Bible states that Jesus was crucified by the Romans in roughly 30 A.D. and was resurrected on a Sunday that has become Easter Sunday. Easter day is also the conclusion of a series of events called the “Passion of the Christ”, that is a 40-day long period of fasting, prayer, and sacrifice that begins with Lent.
Officially Easter is one of the most religious and celebrated holidays within the Christian culture however it is also mixed with many traditions that pre-date Christian beliefs from earlier Pagan times and the Jewish holiday of Passover. The origin of the word Easter is still a debated topic and was not the original name for the holiday. The most widely accepted origin of Easter was from the Anglo-Saxon goddess of spring and fertility, Eastre (or Eeostre). However, one of easter's earlier names was “hebdomada alba” which meant “white week” and it is believed that due to translation issues particularly with people speaking Old High German mistakenly translated the word as “Osteun” (which is a plural for the word “dawn”) which became Easter in English.
For those curious, the reasoning Easter is centered around a bunny, or hare, is due to the holiday's heavy Pagan based history. When Easter was first celebrated by Christians its celebrations were based off Pagan festivals and Easter was a festival within itself. In Pagan tradition bunnies are a symbol of many beliefs, but most prominently fertility, and it is logical to utilize them as a symbol for celebrating new life. Bunnies are also an ancient symbol of the moon and the date of Easter is based around the moon. This association with the moon and an association with the bunny’s burrow being connected as a symbol of Jesus emerging from his tomb has kept the bunny well within Easter's traditions.
Easter eggs on the other hand have a less solid of a connection to Easter, although there are many associations to the eggs that could connect them to the ancient holiday. Many ancient cultures believed the world began as an enormous egg, and with many of these cultures having contact with early Christians it is highly plausible the eggs became a symbol of new life just like the bunny. There are also sources that state many ancient cultures, again many that were directly associated with ancient Christians, utilized eggs as gifts during festival's along with some sources stating eating dyed eggs was a common practice during spring festivals and likely just transitioned into an Easter tradition.
While bunnies and eggs are possibly the most common association with Easter, the most Christian association with Easter would be the Easter lamb. The lamb is connected to the Jewish holiday of Passover where families killed a lamb as a sacrifice. According to beliefs, when Jesus Christ became the “Passover Lamb” for everybody the lamb itself became a symbol of his sacrifice.