PHOENIX — Tuesday marks a special election on two propositions for the city of Phoenix.

Phoenix voters will head to the polls today to make their voices heard on two very important topics: city pensions and the light rail.

The fate of both Proposition 105 and Proposition 106 could be decided on Tuesday. But if you're still undecided, here are the basics of what you need to know.

Prop 105

This prop focuses on the light rail.

A "yes" vote means an end to light rail expansion.

A "no" vote means light rail will continue to spread all over the Valley.

This vote comes as the city is prepared to embark on a $1.3 billion dollar project which includes a transportation hub and 5.5 miles of new track from central Phoenix to south Phoenix down Central Avenue.

If approved, Prop 105 would kill the project in its tracks and divert money towards other projects like roads. However, if the money does not go to light rail, the city would likely miss out on the funding provided by the federal government and the county.

Supporters include business owners along Central Avenue. Many are concerned they will not be able to survive the years of construction and the reduction of the number of lanes of Central Avenue. 

Opponents see light rail as an important infrastructure investment that will help Phoenix join the ranks of other major cities with expansive rail systems while lessening the city's reliance on cars.

MORE: Prop 105: What to do with the Phoenix light rail

PROP 106

This prop deals with the city's $4 billion in unfunded pension debt. That's how much Phoenix will owe retirees in future years, but hasn't covered yet.

Prop. 106 would pay down the public-safety portion of the debt much faster, by capping city spending on most services - almost everything except public safety.

It's actually the latest plan promising to deal with it. Most of the funding for this proposition is coming from out of state.

A "yes" vote would approve the faster paydown of debt.

A "no" vote would stick with the current plan for paying it down.

MORE: Prop. 106 is tough love for Phoenix's pension problem. But who would pay the price?