Two major themes

 

Life and Death is a major theme seen throughout Charlotte's Web and is brought forth by that of the spider, Charlotte's web. ... Even though Wilbur is able to escape his death, Charlotte, the spider who takes care of Wilbur, is not able to escape her own death. 

Charlotte's egg sac is the symbol of renewal after her death.

 

Friendship is the foundation of this novel. Fern's love for Wilbur saved him from being killed. The love of Charlotte saved him from being served up on the Christmas dinner table.