We encounter a variety of symbols every day but rarely stop to think about them.
The flag, for one, is a symbol.
The pause sign on our remote control is a caesura, which calls for stoppage in music and poetry.
If we walk past a church, there is plenty of symbolism there, beginning with the cross.
Corporations such as FedEx use symbols — the arrow between the E and X.
Symbolism is used in literature through an object or reference to add deeper meaning. It can be subtle or obvious. An author may repeatedly use the same object/thought to convey deeper meaning or may use variations of the same object to create a mood or feeling.
Symbols referring to salvation: crosses, angels, clouds.
Symbols referring to death or endings: gravestones, candle blowing out.
Symbols representing moral standards or beliefs: places of worship, banyan trees.
Cultural symbols are specific to particular groups. A Mohawk or an anarchy symbol to indicate a punk rocker. And so on.
Personally, I love it when writers use symbols in their writing to allude to feelings, mood or attitude without directly stating it. Symbolism helps not overstate a point.
In Stranger or Friend, the reader will find Zoe in a church, attending a funeral. The light, the look of the church and people inside it, are all symbolic, there to evoke a feeling of desperation, a description. Same with the palindrome games mentioned, a clue of sorts, but giving too much away would be no fun.
~ As a side note, how are you doing with the Challenge? Symbolically or non-symbolically speaking? :)